CVE-2024-43882 — exec: Fix ToCToU between perm check and set-uid/gid usage
In the Linux kernel, the following vulnerability has been resolved: exec: Fix ToCToU between perm check and set-uid/gid usage When opening a file for exec via do_filp_open(), permission checking is done against the file's metadata at that moment, and on success, a file pointer is passed back. Much later in the execve() code path, the file metadata (specifically mode, uid, and gid) is used to determine if/how to set the uid and gid. However, those values may have changed since the permissions check, meaning the execution may gain unintended privileges. For example, if a file could change permissions from executable and not set-id: ---------x 1 root root 16048 Aug 7 13:16 target to set-id and non-executable: ---S------ 1 root root 16048 Aug 7 13:16 target it is possible to gain root privileges when execution should have been disallowed. While this race condition is rare in real-world scenarios, it has been observed (and proven exploitable) when package managers are updating the setuid bits of installed programs. Such files start with being world-executable but then are adjusted to be group-exec with a set-uid bit. For example, "chmod o-x,u+s target" makes "target" executable only by uid "root" and gid "cdrom", while also becoming setuid-root: -rwxr-xr-x 1 root cdrom 16048 Aug 7 13:16 target becomes: -rwsr-xr-- 1 root cdrom 16048 Aug 7 13:16 target But racing the chmod means users without group "cdrom" membership can get the permission to execute "target" just before the chmod, and when the chmod finishes, the exec reaches brpm_fill_uid(), and performs the setuid to root, violating the expressed authorization of "only cdrom group members can setuid to root". Re-check that we still have execute permissions in case the metadata has changed. It would be better to keep a copy from the perm-check time, but until we can do that refactoring, the least-bad option is to do a full inode_permission() call (under inode lock). It is understood that this is safe against dead-locks, but hardly optimal.
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)+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)
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 (logic error), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
version 2.6.18≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < f50733b45d865f91db90919f8311e2127ce5a0cb≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < 90dfbba89ad4f0d9c9744ecbb1adac4aa2ff4f3e≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < d2a2a4714d80d09b0f8eb6438ab4224690b7121e≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < f6cfc6bcfd5e1cf76115b6450516ea4c99897ae1≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < 9b424c5d4130d56312e2a3be17efb0928fec4d64≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < 15469d46ba34559bfe7e3de6659115778c624759≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < 368f6985d46657b8b466a421dddcacd4051f7ada and 1 more≥ 9167b0b9a0ab7907191523f5a0528e3b9c288e21 and < d5c3c7e26275a2d83b894d30f7582a42853a958f |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
version 6.11-rc3< 4.19.320version 6.11-rc2version 6.11-rc1≥ 6.7 and < 6.10.6≥ 6.2 and < 6.6.47≥ 5.16 and < 6.1.106≥ 5.11 and < 5.15.165 and 2 more≥ 5.5 and < 5.10.224≥ 4.20 and < 5.4.282 |
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 |
|---|---|---|---|---|---|
| 8.4 | CVSS 3.1 | High | 2.5 | 5.9 | 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database |
| 8.4 | CVSS 3.1 | High | — | — | CISA-ADP via CVE Program (cve.org) e CISA ADP |
| 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 | — | — | Linux via CVE Program (cve.org) e CISA ADP |
| 7.0 | CVSS 3.1 | High | 1.0 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.0 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
CVSS:3.1/AV:L/AC:H/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.
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.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- SSVC assessment updated
- Record published
- Fix documented
- Affected products added · linux/linux kernel
- CVSS changed · 7.0
- 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
15 on the record
- git.kernel.org/stable/c/368f6985d46657b8b466a421dddcacd4051f7ada
- git.kernel.org/stable/c/90dfbba89ad4f0d9c9744ecbb1adac4aa2ff4f3e
- git.kernel.org/stable/c/f50733b45d865f91db90919f8311e2127ce5a0cb
- git.kernel.org/stable/c/15469d46ba34559bfe7e3de6659115778c624759
- git.kernel.org/stable/c/d5c3c7e26275a2d83b894d30f7582a42853a958f
- git.kernel.org/stable/c/d2a2a4714d80d09b0f8eb6438ab4224690b7121e
- git.kernel.org/stable/c/f6cfc6bcfd5e1cf76115b6450516ea4c99897ae1
- git.kernel.org/stable/c/9b424c5d4130d56312e2a3be17efb0928fec4d64
- cert-portal.siemens.com/productcert/html/ssa-355557.html
- cert-portal.siemens.com/productcert/html/ssa-613116.html
- github.com/advisories/GHSA-gpj2-qxrh-r55r
- nvd.nist.gov/vuln/detail/CVE-2024-43882
- cert-portal.siemens.com/productcert/html/ssa-265688.html
- lists.debian.org/debian-lts-announce/2024/10/msg00003.html
- lists.debian.org/debian-lts-announce/2025/01/msg00001.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-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 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-2024-43882 is "exec: Fix ToCToU between perm check and set-uid/gid usage", 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 7.0 describes technical severity. EPSS 0.24% 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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