CVE-2024-26883 — bpf: Fix stackmap overflow check on 32-bit arches
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix stackmap overflow check on 32-bit arches The stackmap code relies on roundup_pow_of_two() to compute the number of hash buckets, and contains an overflow check by checking if the resulting value is 0. However, on 32-bit arches, the roundup code itself can overflow by doing a 32-bit left-shift of an unsigned long value, which is undefined behaviour, so it is not guaranteed to truncate neatly. This was triggered by syzbot on the DEVMAP_HASH type, which contains the same check, copied from the hashtab code. The commit in the fixes tag actually attempted to fix this, but the fix did not account for the UB, so the fix only works on CPUs where an overflow does result in a neat truncation to zero, which is not guaranteed. Checking the value before rounding does not have this problem.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.3% (30-day exploitation probability)+2
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Debian Debian Linux, Linux Linux, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Debian | Debian Linux | version 10.0 | Vulnerable | NIST National Vulnerability Database |
| Linux | Linux |
≥ 6183f4d3a0a2ad230511987c6c362ca43ec0055f and < ca1f06e72dec41ae4f76e7b1a8a97265447b46aeversion 5.11≥ 4.14.222 and < 4.15≥ 4.9.258 and < 4.10≥ 5.10.17 and < 5.10.214≥ 5.4.99 and < 5.4.273≥ 4.19.177 and < 4.19.311version 766107351731ae223ebf60ca22bdfeb47ce6acc8 and 9 moreversion 253150830a012adfccf90afcebae8fda5b05a80f≥ 6183f4d3a0a2ad230511987c6c362ca43ec0055f and < 7a4b21250bf79eef26543d35bd390448646c536b≥ 6183f4d3a0a2ad230511987c6c362ca43ec0055f and < 0971126c8164abe2004b8536b49690a0d6005b0a≥ 6183f4d3a0a2ad230511987c6c362ca43ec0055f and < 43f798b9036491fb014b55dd61c4c5c3193267d0≥ 6183f4d3a0a2ad230511987c6c362ca43ec0055f and < 7070b274c7866a4c5036f8d54fcaf315c64ac33a≥ 6183f4d3a0a2ad230511987c6c362ca43ec0055f and < f06899582ccee09bd85d0696290e3eaca9aa042d≥ 8032bf2af9ce26b3a362b9711d15f626ab946a74 and < 15641007df0f0d35fa28742b25c2a7db9dcd6895≥ 7e3a6b820535eb395784060ae26c5af579528fa0 and < 21e5fa4688e1a4d3db6b72216231b24232f75c1d≥ 063c722dd9d285d877e6fd499e753d6224f4c046 and < d0e214acc59145ce25113f617311aa79dda39cb3 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
≥ 6.8 and < 6.8.2≥ 6.7 and < 6.7.11≥ 6.2 and < 6.6.23≥ 5.16 and < 6.1.83≥ 5.11 and < 5.15.153≥ 5.10.17 and < 5.10.214≥ 5.4.99 and < 5.4.273≥ 4.19.177 and < 4.19.311 and 2 more≥ 4.14.222 and < 4.15≥ 4.9.258 and < 4.10 |
Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
CWE-119 · Buffer Errors (Improper Restriction of Operations within Memory Bounds)
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- SSVC assessment updated
- Record published
- Fix documented
- Affected products added · debian/debian linux, linux/linux kernel
- CVSS changed · 7.8
- Source status changed · → Modified
- Record created in this database
- 2024
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
14 on the record
- git.kernel.org/stable/c/d0e214acc59145ce25113f617311aa79dda39cb3
- git.kernel.org/stable/c/7070b274c7866a4c5036f8d54fcaf315c64ac33a
- git.kernel.org/stable/c/7a4b21250bf79eef26543d35bd390448646c536b
- git.kernel.org/stable/c/43f798b9036491fb014b55dd61c4c5c3193267d0
- git.kernel.org/stable/c/0971126c8164abe2004b8536b49690a0d6005b0a
- git.kernel.org/stable/c/15641007df0f0d35fa28742b25c2a7db9dcd6895
- git.kernel.org/stable/c/f06899582ccee09bd85d0696290e3eaca9aa042d
- git.kernel.org/stable/c/21e5fa4688e1a4d3db6b72216231b24232f75c1d
- git.kernel.org/stable/c/ca1f06e72dec41ae4f76e7b1a8a97265447b46ae
- lists.debian.org/debian-lts-announce/2024/06/msg00017.html
- github.com/advisories/GHSA-wwjm-jqc7-c985
- lists.debian.org/debian-lts-announce/2024/06/msg00020.html
- nvd.nist.gov/vuln/detail/CVE-2024-26883
- cert-portal.siemens.com/productcert/html/ssa-265688.html
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 6h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 6h
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2024-26883 is "bpf: Fix stackmap overflow check on 32-bit arches", rated High. It affects Debian Linux (Debian); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.8 describes technical severity. EPSS 0.25% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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