CVE-2026-86805
AT_SECURE programs may load attacker-controlled code via $ORIGIN
- Published
- Updated
- Reserved
- Assigned by
- glibc
Description
A time-of-check to time-of-use (TOCTOU) race condition in the dynamic loader (ld.so) of the GNU C Library (glibc) versions 2.14 through 2.44 allows a local attacker to escalate privileges. When expanding $ORIGIN in DT_RPATH for setuid/setgid (AT_SECURE) programs, glibc validates the lexically normalized search path against the trusted directories but then opens the raw, un-normalized path. On systems where the Linux fs.protected_hardlinks sysctl is disabled, a local attacker who hard-links such a program into an attacker-controlled directory and wins a race to replace an intermediate path component with a symbolic link can direct the loader outside the trusted directory, causing it to load an attacker-controlled shared object and execute arbitrary code with the elevated privileges of the program. Exploitation requires an installed setuid or setgid binary whose DT_RPATH uses $ORIGIN followed by ".." traversal that normalizes into a trusted directory, and the ability to hard-link that binary and win the race by swapping a path component for a symbolic link. Major Linux-based OS distributions ship with fs.protected_hardlinks enabled by default and mitigate the vulnerability.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| glibcCNA (assigner) | 3.1 | Medium6.3 | CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:L |
| NVDNVD · Awaiting Analysis | 3.1 | Medium6.3 | CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:L |
- EPSS (exploitation in 30 days)
- 0.10% · top 99% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.3.
Weakness
Affected products
- affected 2.14 – < 2.45
References (2)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-86805)Record last updated .