5.5

CVE-2025-39715: parisc: Revise gateway LWS calls to probe user read access

Modified
AliasesUBUNTU-CVE-2025-39715DEBIAN-CVE-2025-39715
Published 05-09-2025Last modified 12-05-2026

Vulnerability summary

CVE-2025-39715 is a medium (CVSS 5.5) vulnerability in debian debian_linux. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 4.1% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.15%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 21 · Related 16
DLA-4328-1DSA-6008-1DSA-6009-1MGASA-2025-0234MGASA-2025-0235USN-8028-1

Timeline

  1. 05-09-2025
    PublishedVulnerability first disclosed.
  2. 12-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: parisc: Revise gateway LWS calls to probe user read access We use load and stbys,e instructions to trigger memory reference interruptions without writing to memory. Because of the way read access support is implemented, read access interruptions are only triggered at privilege levels 2 and 3. The kernel and gateway page execute at privilege level 0, so this code never triggers a read access interruption. Thus, it is currently possible for user code to execute a LWS compare and swap operation at an address that is read protected at privilege level 3 (PRIV_USER). Fix this by probing read access rights at privilege level 3 and branching to lws_fault if access isn't allowed.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.15%

Chance of exploitation in the next 30 days

Percentile

4%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.15% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu149 products
  • linuxAll versions (No fix recorded) | < 6.8.0-100.100
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 6.8.0-1046.49
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
  • linux< 6.1.153-1 | < 6.12.48-1 | < 6.16.5-1
  • debian_linuxEOL11.0
Linux2 products
  • linux≥ d0585d742ff2d82accd26c661c60a6d260429c4a, < e8b496c52aa0c6572d88db7cab85aeea6f9c194d | ≥ d0585d742ff2d82accd26c661c60a6d260429c4a, < 8bccf47adbf658293528e86960e6d6f736b1c9f7 | ≥ d0585d742ff2d82accd26c661c60a6d260429c4a, < bc0a24c24ceebabb5ba65900e332233d79e625e6 | ≥ d0585d742ff2d82accd26c661c60a6d260429c4a, < 9b6af875baba9c4679b55f4561e201485451305f | ≥ d0585d742ff2d82accd26c661c60a6d260429c4a, < f6334f4ae9a4e962ba74b026e1d965dfdf8cbef8 | 5.17
  • linux_kernel≥ 5.17, < 6.1.149 | ≥ 6.2, < 6.6.103 | ≥ 6.7, < 6.12.44 | ≥ 6.13, < 6.16.4

3 vendors · 153 products

References

28 links
Show all 28 references