A vulnerability has been found in GNU Binutils 2.45. The affected element is the function elfswapshdr in the library bfd/elfcode.h of the component Linker. The manipulation leads to heap-based buffer overflow. The attack must be carried out locally. The exploit has been disclosed to the public and may be used. The identifier of the patch is 9ca499644a21ceb3f946d1c179c38a83be084490. To fix this issue, it is recommended to deploy a patch. The code maintainer replied with "[f]ixed for 2.46".

CVE-2024-42516 - this is the "complete" fix for the CVE-2023-38709 response splitting issue. The patch issued upstream for CVE-2023-38709 did not fix the vulnerability.

A use-after-free vulnerability was found in libxslt while parsing xsl nodes that may lead to the dereference of expired pointers and application crash.

Accessibility. A privacy issue was addressed by removing sensitive data.

In the Linux kernel, the following vulnerability has been resolved:

mm: fix zswap writeback race condition

The zswap writeback mechanism can cause a race condition resulting in memory corruption, where a swapped out page gets swapped in with data that was written to a different page.

The race unfolds like this: 1. a page with data A and swap offset X is stored in zswap 2. page A is removed off the LRU by zpool driver for writeback in zswap-shrink work, data for A is mapped by zpool driver 3. user space program faults and invalidates page entry A, offset X is considered free 4. kswapd stores page B at offset X in zswap (zswap could also be full, if so, page B would then be IOed to X, then skip step 5.) 5. entry A is replaced by B in tree->rbroot, this doesn't affect the local reference held by zswap-shrink work 6. zswap-shrink work writes back A at X, and frees zswap entry A 7. swapin of slot X brings A in memory instead of B

The fix: Once the swap page cache has been allocated (case ZSWAPSWAPCACHENEW), zswap-shrink work just checks that the local zswapentry reference is still the same as the one in the tree. If it's not the same it means that it's either been invalidated or replaced, in both cases the writeback is aborted because the local entry contains stale data.

Reproducer: I originally found this by running stress overnight to validate my work on the zswap writeback mechanism, it manifested after hours on my test machine. The key to make it happen is having zswap writebacks, so whatever setup pumps /sys/kernel/debug/zswap/writtenbackpages should do the trick.

In order to reproduce this faster on a vm, I setup a system with ~100M of available memory and a 500M swap file, then running stress --vm 1 --vm-bytes 300000000 --vm-stride 4000 makes it happen in matter of tens of minutes. One can speed things up even more by swinging /sys/module/zswap/parameters/maxpoolpercent up and down between, say, 20 and 1; this makes it reproduce in tens of seconds. It's crucial to set --vm-stride to something other than 4096 otherwise stress won't realize that memory has been corrupted because all pages would have the same data.

A flaw has been found in GNU Binutils 2.45. Impacted is the function bfdelfparseehframe of the file bfd/elf-eh-frame.c of the component Linker. Executing manipulation can lead to heap-based buffer overflow. The attack is restricted to local execution. The exploit has been published and may be used. This patch is called ea1a0737c7692737a644af0486b71e4a392cbca8. A patch should be applied to remediate this issue. The code maintainer replied with "[f]ixed for 2.46".

In the Linux kernel, the following vulnerability has been resolved:

sched/membarrier: reduce the ability to hammer on sysmembarrier

On some systems, sysmembarrier can be very expensive, causing overall slowdowns for everything. So put a lock on the path in order to serialize the accesses to prevent the ability for this to be called at too high of a frequency and saturate the machine.

802.1X. An authentication issue was addressed with improved state management.

Last updated 20 August 2025

Accounts. The issue was addressed with improved checks.

Dear Linux Developers,

We're reaching out to you as part of the disclosure process of our research.

In our research, which we will present at IEEE Security & Privacy in May 2024, we found that attackers can not only create TCP-spoofed connections (which was already known), but can also reliably transmit IP-spoofed data over such connections. This has security implications for applications that rely on TCP endpoint IP addresses, such as firewalling or host-based authentication (e.g., SMTP/SPF, of DBs).

We basically discovered two TCP spoofing primitives. First, attackers can bruteforce the server-chosen send window by acknowledging data that was never sent (what we call "ghost ACKs"; see Figure 3 in the paper). Second, we show that there are side channels that allow the attacker to leak the otherwise-secret server-chosen initial sequence number (ISN). One of these side channels leverages TCP SYN cookies.

We believe that the TCP/IP stack can take countermeasures to prevent such attacks, or at least make them harder. For example, we think that TCP endpoints should ignore ghost ACKs, and have some ideas to randomize the TCP backlog queue to prevent the SYN cookie side channel.

At the same time, we have disclosed our findings to the IETF folks and hope that they have helpful feedback for us.

Prior to Apache HTTP Server 2.4.55, a malicious backend can cause the response headers to be truncated early, resulting in some headers being incorporated into the response body. If the later headers have any security purpose, they will not be interpreted by the client.

Inconsistent Interpretation of HTTP Requests ('HTTP Request Smuggling') vulnerability in modproxyajp of Apache HTTP Server allows an attacker to smuggle requests to the AJP server it forwards requests to. This issue affects Apache HTTP Server Apache HTTP Server 2.4 version 2.4.54 and prior versions.

CPython 3.9 and earlier doesn't disallow configuring an empty list ("[]") for SSLContext.setnpnprotocols() which is an invalid value for the underlying OpenSSL API. This results in a buffer over-read when NPN is used (see CVE-2024-5535 for OpenSSL). This vulnerability is of low severity due to NPN being not widely used and specifying an empty list likely being uncommon in-practice (typically a protocol name would be configured).

Accessibility. A privacy issue was addressed with improved private data redaction for log entries.

Last updated 31 October 2024

An out-of-bounds memory write flaw in the Linux kernel’s USB Monitor component was found in how a user with access to the /dev/usbmon can trigger it by an incorrect write to the memory of the usbmon. This flaw allows a local user to crash or potentially escalate their privileges on the system.

A fundamental design flaw within the RADIUS protocol has been proven to be exploitable, compromising the integrity in the RADIUS Access-Request process. The attack allows a malicious user to modify packets in a way that would be indistinguishable to a RADIUS client or server. To be successful, the attacker must have the ability to inject themselves between the client and server.

Heap-based buffer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to have unspecified impact via vectors involving OPTION6RD parsing.

Validating the order of the public keys in the Diffie-Hellman Key Agreement Protocol, when an approved safe prime is used, allows remote attackers (from the client side) to trigger unnecessarily expensive server-side DHE modular-exponentiation calculations. The client may cause asymmetric resource consumption. The basic attack scenario is that the client must claim that it can only communicate with DHE, and the server must be configured to allow DHE and validate the order of the public key.

Last updated 18 September 2024

Heap-based buffer overflow in the DHCP client (udhcpc) in BusyBox before 1.25.0 allows remote attackers to have unspecified impact via vectors involving OPTION6RD parsing.

Race condition in Seamless Firmware Updates for some Intel(R) reference platforms may allow a privileged user to potentially enable denial of service via local access.

Race condition in Seamless Firmware Updates for some Intel(R) reference platforms may allow a privileged user to potentially enable denial of service via local access.

CVE-2024-39279 Insufficient granularity of access control in UEFI firmware in some Intel(R) processors may allow a authenticated user to potentially enable denial of service via local access. CVE-2024-28047 Improper input validation in UEFI firmware for some Intel(R) Processors may allow a privileged user to potentially enable information disclosure via local access.

CVE-2024-39279 Insufficient granularity of access control in UEFI firmware in some Intel(R) processors may allow a authenticated user to potentially enable denial of service via local access. CVE-2024-28047 Improper input validation in UEFI firmware for some Intel(R) Processors may allow a privileged user to potentially enable information disclosure via local access.

CVE-2024-39279 Insufficient granularity of access control in UEFI firmware in some Intel(R) processors may allow a authenticated user to potentially enable denial of service via local access. CVE-2024-28047 Improper input validation in UEFI firmware for some Intel(R) Processors may allow a privileged user to potentially enable information disclosure via local access.

Improper input validation in UEFI firmware for some Intel(R) Processors may allow a privileged user to enable information disclosure or denial of service via local access.

Improper input validation in UEFI firmware for some Intel(R) Processors may allow a privileged user to enable information disclosure or denial of service via local access.

In the Linux kernel, the following vulnerability has been resolved: tcp: do not accept ACK of bytes we never sent This patch is based on a detailed report and ideas from Yepeng Pan and Christian Rossow. ACK seq validation is currently following RFC 5961 5.2 guidelines: The ACK value is considered acceptable only if it is in the range of ((SND.UNA - MAX.SND.WND) <= SEG.ACK <= SND.NXT). All incoming segments whose ACK value doesn't satisfy the above condition MUST be discarded and an ACK sent back. It needs to be noted that RFC 793 on page 72 (fifth check) says: "If the ACK is a duplicate (SEG.ACK < SND.UNA), it can be ignored. If the ACK acknowledges something not yet sent (SEG.ACK > SND.NXT) then send an ACK, drop the segment, and return". The "ignored" above implies that the processing of the incoming data segment continues, which means the ACK value is treated as acceptable. This mitigation makes the ACK check more stringent since any ACK < SND.UNA wouldn't be accepted, instead only ACKs that are in the range ((SND.UNA - MAX.SND.WND) <= SEG.ACK <= SND.NXT) get through. This can be refined for new (and possibly spoofed) flows, by not accepting ACK for bytes that were never sent. This greatly improves TCP security at a little cost. I added a Fixes: tag to make sure this patch will reach stable trees, even if the 'blamed' patch was adhering to the RFC. tp->bytesacked was added in linux-4.2 Following packetdrill test (courtesy of Yepeng Pan) shows the issue at hand: 0 socket(..., SOCKSTREAM, IPPROTOTCP) = 3 +0 setsockopt(3, SOLSOCKET, SOREUSEADDR, [1], 4) = 0 +0 bind(3, ..., ...) = 0 +0 listen(3, 1024) = 0 // ---------------- Handshake ------------------- // // when window scale is set to 14 the window size can be extended to // 65535 (2^14) = 1073725440. Linux would accept an ACK packet // with ack number in (ServerISN+1-1073725440. ServerISN+1) // ,though this ack number acknowledges some data never // sent by the server. +0 < S 0:0(0) win 65535 +0 > S. 0:0(0) ack 1 <...> +0 < . 1:1(0) ack 1 win 65535 +0 accept(3, ..., ...) = 4 // For the established connection, we send an ACK packet, // the ack packet uses ack number 1 - 1073725300 + 2^32, // where 2^32 is used to wrap around. // Note: we used 1073725300 instead of 1073725440 to avoid possible // edge cases. // 1 - 1073725300 + 2^32 = 3221241997 // Oops, old kernels happily accept this packet. +0 < . 1:1001(1000) ack 3221241997 win 65535 // After the kernel fix the following will be replaced by a challenge ACK, // and prior malicious frame would be dropped. +0 > . 1:1(0) ack 1001