CVE-2026-80560openrisc: signal: do not restore privileged SR bits on sigreturn
- 7.8HighCVSS base score
- 0.13%Exploitation in 30 daysEPSS · top 97% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: openrisc: signal: do not restore privileged SR bits on sigreturn restore_sigcontext() copies the whole supervision register (SR) from the signal frame and only clears SPR_SR_SM before the value is reloaded into the hardware SR (through ESR and l.rfe) on the return to user space. All other SR bits are left under user control. An unprivileged task can thus return from a signal handler through a crafted sigframe that clears SPR_SR_DME. With the data MMU disabled the CPU performs no translation or protection on data accesses, so the task gains read and write access to arbitrary physical memory, a local privilege escalation. SPR_SR_IME, SPR_SR_SUMRA, SPR_SR_LEE, SPR_SR_EPH and the cache-enable bits are exposed the same way. The ptrace GPR regset already refuses any change to SR for exactly this reason. Restore only the arithmetic flag bits (F, CY, OV) from the signal frame and take every privileged control bit from the SR the kernel saved on signal entry. Verified with qemu-system-or1k -M or1k-sim: before this change an unprivileged PoC clears SPR_SR_DME in rt_sigreturn and writes a marker to physical address 0x03000000 (beyond the kernel's mem=32M); afterwards the same PoC receives SIGSEGV and physical memory is unchanged.
Timeline
ID reserved
By Linux
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.13% · top 97% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.8.
Affected products
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < bc2e24ba6e167ccf374a197457aa5640a802f429
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < cf1b5514ddf9df098ce7e3741fc9679fd85a4ec6
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < cd8b43a71755c516f5c1f265a103438ae9ab15be
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < b4d73c3848bae9084fa8b9b2aa76d99a7d8eb17d
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < 89a91b30685c0493b0fa2b47d0ab41061a63069d
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < a88d688be8d7f03cbf927f2ab454ea9fa58d2979
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < 212fc482ddd7f9ccdd74a05eab1cac849350dcd6
- affected ac689eb7f9d4e270d1365853b82eece669387e2c – < 32ef1b30ad736519f7a207bcc2986f3d4129d972
- affected 3.1
- unaffected < 3.1
- unaffected 5.10.266 – ≤ 5.10.*
- unaffected 5.15.217 – ≤ 5.15.*
- unaffected 6.1.184 – ≤ 6.1.*
- unaffected 6.6.153 – ≤ 6.6.*
- unaffected 6.12.105 – ≤ 6.12.*
- unaffected 6.18.46 – ≤ 6.18.*
- unaffected 7.1.10 – ≤ 7.1.*
- unaffected 7.2 – ≤ *
References
References8
- https://git.kernel.org/stable/c/bc2e24ba6e167ccf374a197457aa5640a802f429 (opens in a new tab)
- https://git.kernel.org/stable/c/cf1b5514ddf9df098ce7e3741fc9679fd85a4ec6 (opens in a new tab)
- https://git.kernel.org/stable/c/cd8b43a71755c516f5c1f265a103438ae9ab15be (opens in a new tab)
- https://git.kernel.org/stable/c/b4d73c3848bae9084fa8b9b2aa76d99a7d8eb17d (opens in a new tab)
- https://git.kernel.org/stable/c/89a91b30685c0493b0fa2b47d0ab41061a63069d (opens in a new tab)
- https://git.kernel.org/stable/c/a88d688be8d7f03cbf927f2ab454ea9fa58d2979 (opens in a new tab)
- https://git.kernel.org/stable/c/212fc482ddd7f9ccdd74a05eab1cac849350dcd6 (opens in a new tab)
- https://git.kernel.org/stable/c/32ef1b30ad736519f7a207bcc2986f3d4129d972 (opens in a new tab)
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)
- EUVD EUVD-2026-66475 (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://cveledger.app/cve/CVE-2026-80560)Record last updated .