CVE-2025-38502: Linux kernel · bpf: Fix oob access in cgroup local storage
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.8 High · fixed in 5.15.0-1097.104~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 7% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1097.104~20.04.1, 5.15.0-1102.111~20.04.1, 5.15.0-1097.106~20.04.1 +56
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 16 Aug 2025
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.
Patches and advisories
- ubuntu.com/security/notices/USN-7909-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7910-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7910-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7933-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7938-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8100-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-2 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 25.10linux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=questingOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-aws-6.14pkg:deb/ubuntu/linux-aws-6.14?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Ubuntu 24.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=nobleOther threats | Affected
| Fixed in
|
Ubuntu 24.04 LTSlinux-azure-6.11pkg:deb/ubuntu/linux-azure-6.11?arch=source&distro=nobleOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix oob access in cgroup local storage Lonial reported that an out-of-bounds access in cgroup local storage can be crafted via tail calls. Given two programs each utilizing a cgroup local storage with a different value size, and one program doing a tail call into the other. The verifier will validate each of the indivial programs just fine. However, in the runtime context the bpf_cg_run_ctx holds an bpf_prog_array_item which contains the BPF program as well as any cgroup local storage flavor the program uses. Helpers such as bpf_get_local_storage() pick this up from the runtime context: ctx = container_of(current->bpf_ctx, struct bpf_cg_run_ctx, run_ctx); storage = ctx->prog_item->cgroup_storage[stype]; if (stype == BPF_CGROUP_STORAGE_SHARED) ptr = &READ_ONCE(storage->buf)->data[0]; else ptr = this_cpu_ptr(storage->percpu_buf); For the second program which was called from the originally attached one, this means bpf_get_local_storage() will pick up the former program's map, not its own. With mismatching sizes, this can result in an unintended out-of-bounds access. To fix this issue, we need to extend bpf_map_owner with an array of storage_cookie[] to match on i) the exact maps from the original program if the second program was using bpf_get_local_storage(), or ii) allow the tail call combination if the second program was not using any of the cgroup local storage maps.
References
- ubuntu.com/security/CVE-2025-38502 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2025-38502 (opens in a new tab)
- git.kernel.org/linus/abad3d0bad72a52137e0c350c59542d75ae4f513 (opens in a new tab)
- git.kernel.org/stable/c/19341d5c59e8c7e8528e40f8663e99d67810473c (opens in a new tab)
- git.kernel.org/stable/c/abad3d0bad72a52137e0c350c59542d75ae4f513 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-7910-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-7910-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-7933-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-7909-5 (opens in a new tab)
- ubuntu.com/security/notices/USN-7938-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8100-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8095-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8125-1 (opens in a new tab)