Abnormal termination of an application can a cause a denial of service.
Applications performing certificate name checks (e.g., TLS clients checking server certificates) may attempt to read an invalid memory address when comparing the expected name with an otherName subject alternative name of an X.509 certificate. This may result in an exception that terminates the application program.
Note that basic certificate chain validation (signatures, dates, ...) is not affected, the denial of service can occur only when the application also specifies an expected DNS name, Email address or IP address.
TLS servers rarely solicit client certificates, and even when they do, they generally don't perform a name check against a "reference identifier" (expected identity), but rather extract the presented identity after checking the certificate chain. So TLS servers are generally not affected and the severity of the issue is Moderate.
The FIPS modules in 3.3, 3.2, 3.1 and 3.0 are not affected by this issue. OpenSSL 1.1.1 and 1.0.2 are also not affected by this issue.
OpenSSL 3.3, 3.2, 3.1 and 3.0 are vulnerable to this issue.
OpenSSL 3.3 users should upgrade to OpenSSL 3.3.2
OpenSSL 3.2 users should upgrade to OpenSSL 3.2.3
OpenSSL 3.1 users should upgrade to OpenSSL 3.1.7
OpenSSL 3.0 users should upgrade to OpenSSL 3.0.15
A security regression (CVE-2006-5051) was discovered in OpenSSH's server (sshd). There is a race condition which can lead sshd to handle some signals in an unsafe manner. An unauthenticated, remote attacker may be able to trigger it by failing to authenticate within a set time period.
A use-after-free vulnerability in the Linux kernel's netfilter: nftables component can be exploited to achieve local privilege escalation.
The nftverdictinit() function allows positive values as drop error within the hook verdict, and hence the nfhookslow() function can cause a double free vulnerability when NFDROP is issued with a drop error which resembles NFACCEPT.
We recommend upgrading past commit f342de4e2f33e0e39165d8639387aa6c19dff660.
OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kexalgorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states "remote code execution is theoretically possible."
A flaw was found in OpenSSL. It is possible to trigger an infinite loop by crafting a certificate that has invalid elliptic curve parameters. Since certificate parsing happens before verification of the certificate signature, any process that parses an externally supplied certificate may be subject to a denial of service attack.
Internally libssl in OpenSSL calls X509verifycert() on the client side to verify a certificate supplied by a server. That function may return a negative return value to indicate an internal error (for example out of memory). Such a negative return value is mishandled by OpenSSL and will cause an IO function (such as SSLconnect() or SSLdohandshake()) to not indicate success and a subsequent call to SSLgeterror() to return the value SSLERRORWANTRETRYVERIFY. This return value is only supposed to be returned by OpenSSL if the application has previously called SSLCTXsetcertverifycallback(). Since most applications do not do this the SSLERRORWANTRETRYVERIFY return value from SSLgeterror() will be totally unexpected and applications may not behave correctly as a result. The exact behaviour will depend on the application but it could result in crashes, infinite loops or other similar incorrect responses. This issue is made more serious in combination with a separate bug in OpenSSL 3.0 that will cause X509verifycert() to indicate an internal error when processing a certificate chain. This will occur where a certificate does not include the Subject Alternative Name extension but where a Certificate Authority has enforced name constraints. This issue can occur even with valid chains. By combining the two issues an attacker could induce incorrect, application dependent behaviour. Fixed in OpenSSL 3.0.1 (Affected 3.0.0).
A flaw was found in Linux Kernel because access to the global variable fgconsole is not properly synchronized leading to a use after free in confontop.
GNU Wget through 1.21.1 does not omit the Authorization header upon a redirect to a different origin, a related issue to CVE-2018-1000007.
In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.
GNU C Library (aka glibc or libc6) is vulnerable to a denial of service, caused by an error when processing some invalid inputs from several IBM character sets in the iconv function. By sending invalid multi-byte input sequences in IBM1364, IBM1371, IBM1388, IBM1390, IBM1399 encodings, a local authenticated attacker could exploit this vulnerability to cause the application to enter into an infinite loop.
BIND servers are vulnerable if they are running an affected version and are configured to use GSS-TSIG features. In a configuration which uses BIND's default settings the vulnerable code path is not exposed, but a server can be rendered vulnerable by explicitly setting valid values for the tkey-gssapi-keytab or tkey-gssapi-credentialconfiguration options. Although the default configuration is not vulnerable, GSS-TSIG is frequently used in networks where BIND is integrated with Samba, as well as in mixed-server environments that combine BIND servers with Active Directory domain controllers. The most likely outcome of a successful exploitation of the vulnerability is a crash of the named process. However, remote code execution, while unproven, is theoretically possible. Affects: BIND 9.5.0 -> 9.11.27, 9.12.0 -> 9.16.11, and versions BIND 9.11.3-S1 -> 9.11.27-S1 and 9.16.8-S1 -> 9.16.11-S1 of BIND Supported Preview Edition. Also release versions 9.17.0 -> 9.17.1 of the BIND 9.17 development branch
GNU glibc is vulnerable to a denial of service, caused by a buffer over-read in iconv feature. By sending a specially-crafted request, a remote attacker could exploit this vulnerability to cause a SIGSEGV.
An issue was discovered in the Linux kernel before 5.7.3, related to mm/gup.c and mm/hugememory.c. The getuserpages (aka gup) implementation, when used for a copy-on-write page, does not properly consider the semantics of read operations and therefore can grant unintended write access, aka CID-17839856fd58.