CVE-2026-68158: libceph: Fix multiplication overflow in decode_new_up_state_weight()
In the Linux kernel, the following vulnerability has been resolved:
libceph: Fix multiplication overflow in decodenewupstateweight()
If a message of type CEPHMSGOSDMAP contains a (maliciously) corrupted osdmap, out-of-bounds memory accesses may occur in decodenewupstateweight(). This happens because the bounds check for the newstate part is based on calculating its length depending on a len value read from the incoming message. This calculation may overflow leading to an incorrect bounds check. Subsequently, out-of-bounds reads may occur when decoding this part.
This patch switches the multiplication to use checkmuloverflow() to abort processing the osdmap if an overflow occurred. Therefore, osdmaps/messages containing large values for len that result in a multiplication overflow are treated as invalid.
[ idryomov: rename newstatelen -> newstateitemsize, formatting ]
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Linux kernelto a version that resolves this vulnerability.Patch libceph: Fix multiplication overflow in decode_new_up_state_weight()
Event History
Frequently Asked Questions
What is the severity of CVE-2026-68158?
The severity of CVE-2026-68158 is rated as risk 33.
What type of vulnerability is CVE-2026-68158?
CVE-2026-68158 is a multiplication overflow vulnerability that affects the decode_new_up_state_weight() function in the Linux kernel.
How does CVE-2026-68158 impact the system?
CVE-2026-68158 may lead to out-of-bounds memory accesses if a maliciously corrupted osdmap is processed.
How do I fix CVE-2026-68158?
To fix CVE-2026-68158, update the Linux kernel to the latest version that addresses this specific vulnerability.
When was CVE-2026-68158 published?
CVE-2026-68158 was published on August 10, 2026.