CVE-2026-68158: Linux kernel · libceph: Fix multiplication overflow in decode_new_up_state_weight()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 9.8 Critical · fixed in f6961070c326bd158c38fa48756cde2bd78c4aaa : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 14:18 UTC
- EPSS
- 0.7% chance of exploitation in 30 days – higher than 53% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers can reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in f6961070c326bd158c38fa48756cde2bd78c4aaa, e4473751cc37db41f3f7da25d64a23e0c74570f1, bee4b5b53e7bff0467fd916cc44c9b190733c6bd +13
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: libceph: Fix multiplication overflow in decode_new_up_state_weight() If a message of type CEPH_MSG_OSD_MAP contains a (maliciously) corrupted osdmap, out-of-bounds memory accesses may occur in decode_new_up_state_weight(). This happens because the bounds check for the new_state 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 check_mul_overflow() 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 new_state_len -> new_state_item_size, formatting ]
References
- git.kernel.org/stable/c/2ceee3b77b83052648c40fef965f836fd7699d26 (opens in a new tab)
- git.kernel.org/stable/c/e4473751cc37db41f3f7da25d64a23e0c74570f1 (opens in a new tab)
- git.kernel.org/stable/c/f6961070c326bd158c38fa48756cde2bd78c4aaa (opens in a new tab)
- git.kernel.org/stable/c/05c90e059269f087becfcce23348496085835c29 (opens in a new tab)
- git.kernel.org/stable/c/143ba49ead77ec483c0326f8aaad8649874e99c4 (opens in a new tab)
- git.kernel.org/stable/c/1732d89dfcd74f6fde9ce70900d316c4a151c153 (opens in a new tab)
- git.kernel.org/stable/c/bee4b5b53e7bff0467fd916cc44c9b190733c6bd (opens in a new tab)
- git.kernel.org/stable/c/98917a499ec7064c14fc56d180a4fd636fc2784c (opens in a new tab)