CVE-2026-43453 — netfilter: nft_set_pipapo: fix stack out-of-bounds read in pipapo_drop()
In the Linux kernel, the following vulnerability has been resolved: netfilter: nft_set_pipapo: fix stack out-of-bounds read in pipapo_drop() pipapo_drop() passes rulemap[i + 1].n to pipapo_unmap() as the to_offset argument on every iteration, including the last one where i == m->field_count - 1. This reads one element past the end of the stack-allocated rulemap array (declared as rulemap[NFT_PIPAPO_MAX_FIELDS] with NFT_PIPAPO_MAX_FIELDS == 16). Although pipapo_unmap() returns early when is_last is true without using the to_offset value, the argument is evaluated at the call site before the function body executes, making this a genuine out-of-bounds stack read confirmed by KASAN: BUG: KASAN: stack-out-of-bounds in pipapo_drop+0x50c/0x57c [nf_tables] Read of size 4 at addr ffff8000810e71a4 This frame has 1 object: [32, 160) 'rulemap' The buggy address is at offset 164 -- exactly 4 bytes past the end of the rulemap array. Pass 0 instead of rulemap[i + 1].n on the last iteration to avoid the out-of-bounds read.
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 0.2% (30-day exploitation probability)+1
- 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.
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)
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 (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 |
|---|---|---|---|---|
| Linux | Linux |
version 5.6≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < d6d8cd2db236a9dd13dbc2d05843b3445cc964b5≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 324b749aa5b2d516ccfab933df9d3f56e7807f5f≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < e047f6fbb975f685d6c9fcef95b3b7787a79b46d≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < dfbdac719198778b581bc0dd055df2542edb8c62≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 0a55d62cdb628923d8a21724374a70c76ac7d19d≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 60c1d18781e37bfb96290b86510eb01c5fa24d75≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 57fb87ca095d5127cd7a27583b8ec43dcf7c9e9e and 1 more≥ 3c4287f62044a90e73a561aa05fc46e62da173da and < 1957e793196e7f8557374fd4eda53abcbb42e1c0 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 7.0-rc3≥ 5.6 and < 5.10.253version 7.0-rc2version 7.0-rc1≥ 6.19 and < 6.19.9≥ 6.13 and < 6.18.19≥ 6.7 and < 6.12.78≥ 6.2 and < 6.6.130 and 2 more≥ 5.16 and < 6.1.167≥ 5.11 and < 5.15.203 |
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 |
|---|---|---|---|---|---|
| 7.1 | CVSS 3.1 | High | 1.8 | 5.2 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.17%
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
- Record published
- Fix documented
- CVSS changed · 7.1
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
8 on the record
- git.kernel.org/stable/c/1957e793196e7f8557374fd4eda53abcbb42e1c0
- git.kernel.org/stable/c/0a55d62cdb628923d8a21724374a70c76ac7d19d
- git.kernel.org/stable/c/e047f6fbb975f685d6c9fcef95b3b7787a79b46d
- git.kernel.org/stable/c/57fb87ca095d5127cd7a27583b8ec43dcf7c9e9e
- git.kernel.org/stable/c/d6d8cd2db236a9dd13dbc2d05843b3445cc964b5
- git.kernel.org/stable/c/dfbdac719198778b581bc0dd055df2542edb8c62
- git.kernel.org/stable/c/324b749aa5b2d516ccfab933df9d3f56e7807f5f
- git.kernel.org/stable/c/60c1d18781e37bfb96290b86510eb01c5fa24d75
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 15h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 15h
- 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 CISA SSVC assessment.
- 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-2026-43453 is "netfilter: nft_set_pipapo: fix stack out-of-bounds read in pipapo_drop()", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.1 describes technical severity. EPSS 0.17% 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.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.