Buffer overflow in FreeBSD
CVE-2026-58088
The ELF core dump code counted the number of dumpable VM map entries, allocated a buffer for the corresponding program headers, then iterated over the map a second time to populate them. A process sharing the address space via rfork(2) can mutate the map between the two passes, causing the second pass to write program headers past the end of the buffer. An unprivileged local user sharing an address space with a process that dumps core can trigger an out-of-bounds write on the kernel heap, potentially leading to privilege escalation.
Vulnerability class: Race Condition
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.001 (1.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 1st percentile — 1.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: -0.000
Affected products
- FreeBSD — versions 15.0, 14.4, 15.1
Weakness classification (CWE)
References
- security.freebsd.org/advisories/FreeBSD-SA-26:55.elf.asc (vendor-advisory, Mailing List, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-58088?
- CVE-2026-58088 is a high-severity vulnerability in FreeBSD, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.4/10. Published 2026-08-19.
- How severe is CVE-2026-58088?
- High severity. CVSS v3 base score is 7.4 out of 10.