7.5

CVE-2026-45859: linux Uncontrolled Resource Consumption

CVSS: 7.5v3.1HighModified
AliasesUBUNTU-CVE-2026-45859DEBIAN-CVE-2026-45859
Published 27-05-2026Last modified 19-10-2026
Open JSON

Vulnerability summary

CVE-2026-45859 is a high (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in linux. EPSS estimates a 0.61% chance of exploitation in the next 30 days, higher than 48.3% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.61%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 19 · Related 18
OPENSUSE-SU-2026:21555-1RHSA-2026:83207SUSE-SU-2026:23066-1SUSE-SU-2026:23068-1SUSE-SU-2026:23221-1SUSE-SU-2026:23231-1

Timeline

  1. 27-05-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation Ulrich reports a regression with nfqueue: If an application did not set the 'F_GSO' capability flag and a gso packet with an unconfirmed nf_conn entry is received all packets are now dropped instead of queued, because the check happens after skb_gso_segment(). In that case, we did have exclusive ownership of the skb and its associated conntrack entry. The elevated use count is due to skb_clone happening via skb_gso_segment(). Move the check so that its peformed vs. the aggregated packet. Then, annotate the individual segments except the first one so we can do a 2nd check at reinject time. For the normal case, where userspace does in-order reinjects, this avoids packet drops: first reinjected segment continues traversal and confirms entry, remaining segments observe the confirmed entry. While at it, simplify nf_ct_drop_unconfirmed(): We only care about unconfirmed entries with a refcnt > 1, there is no need to special-case dying entries. This only happens with UDP. With TCP, the only unconfirmed packet will be the TCP SYN, those aren't aggregated by GRO. Next patch adds a udpgro test case to cover this scenario.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.61%

Chance of exploitation in the next 30 days

Percentile

48%

Versus all other CVEs

30-day change

0.00 pp

From 0.61% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.61%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu145 products
  • linuxAll versions (No fix recorded) | < 6.8.0-134.134
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 6.8.0-1060.63
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb, < 79b713ef4261a8ead96af4703f89d0b5f25532e2 | ≥ 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb, < 23901aa6b8a2f294c4b774436b4691f3ff863a8f | ≥ 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb, < b740e7ddd7ca0dbfeafca3f5e52717206cf28524 | ≥ 7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb, < 207b3ebacb6113acaaec0d171d5307032c690004 | 6c4a0ba674f410ab99a30a16f32dac0ebfed5cd3 | 6dcc8ba8a6074bb79040f502dc66ad23a58a1c86 | 74e6eb7fd27ef1ccc68041dbc66e6d80d2e4a1a0 | 025b3326c5c409b372d0103ad30f174e55adbd1b | ≥ 5.15.166, < 5.16 | ≥ 6.1.107, < 6.2 | ≥ 6.6.48, < 6.7 | ≥ 6.10.7, < 6.11 | 6.11
  • linux_kernelEOL≥ 5.15.166, < 5.16 | ≥ 6.1.107, < 6.2 | ≥ 6.6.48, < 6.7 | ≥ 6.10.7, < 6.11 | ≥ 6.11.1, < 6.12.75 | ≥ 6.13, < 6.18.14 | ≥ 6.19, < 6.19.4 | 6.11 | 6.11:rc4 | 6.11:rc5 | 6.11:rc6 | 6.11:rc7
Debian1 product
  • linuxAll versions (No fix recorded) | < 6.12.85-1 | < 6.18.14-1

3 vendors · 148 products

References

20 links
Show all 20 references