6.5

CVE-2026-8458: wrong reuse for different services

Modified
AliasesALPINE-CVE-2026-8458UBUNTU-CVE-2026-8458DEBIAN-CVE-2026-8458
Published 03-07-2026Last modified 15-09-2026

Vulnerability summary

CVE-2026-8458 is a medium (CVSS 6.5) vulnerability in curl. EPSS estimates a 0.37% chance of exploitation in the next 30 days, higher than 31.1% of scored vulnerabilities. 1 public exploit is recorded.

Priority
Routine

Not severe (CVSS 6.5, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.37%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits1reference

Advisory lineage

Upstream 0 · Downstream 16 · Related 13
OPENSUSE-SU-2026:11230-1OPENSUSE-SU-2026:21272-1RHSA-2026:29017RHSA-2026:34975RHSA-2026:69125RHSA-2026:69126

Timeline

  1. 03-07-2026
    PublishedVulnerability first disclosed.
  2. 15-09-2026
    Last modifiedVulnerability information updated.

Description

libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services". libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When reusing a connection a range of criteria must be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different services.

CVSS metrics

7 scores · 7 sources · 1 version

EPSS trend

Probability

0.37%

Chance of exploitation in the next 30 days

Percentile

31%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.37% 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

1 found
  • referenceUnverified

    Exploit Reference (hackerone.com)

    Maturity: unknown

Weaknesses

CWE · root cause

Affected systems

Version check

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

Chainguard11 products
  • eco-python-curl< 8.21.0-r0
  • eco-python-curl-minimal< 8.21.0-r0
  • eco-python-curl-minimal-bin< 8.21.0-r0
  • eco-python-curl-minimal-dev< 8.21.0-r0
  • eco-python-curl-minimal-doc< 8.21.0-r0
Alpine1 product
  • curl≥ 7.46.0, < 8.22.0-r0 | ≥ 7.46.0, < 8.21.0-r0
Curl1 product
  • curl≥ 7.43.0, < 8.14.2 | ≥ 8.15.0, < 8.16.1 | ≥ 8.17.0, < 8.20.1 | ≥ 97c272e5d173ad5f706443e2477f0a84f0044edd, < 5e99b73cf441d9c369768b9cd48b5389b9a2503d | 8.20.0 | 8.19.0 | 8.18.0 | 8.17.0 | 8.16.0 | 8.15.0 | 8.14.1 | 8.14.0 | 8.13.0 | 8.12.1 | 8.12.0 | 8.11.1 | 8.11.0 | 8.10.1 | 8.10.0 | 8.9.1 | 8.9.0 | 8.8.0 | 8.7.1 | 8.7.0 | 8.6.0 | 8.5.0 | 8.4.0 | 8.3.0 | 8.2.1 | 8.2.0 | 8.1.2 | 8.1.1 | 8.1.0 | 8.0.1 | 8.0.0 | 7.88.1 | 7.88.0 | 7.87.0 | 7.86.0 | 7.85.0 | 7.84.0 | 7.83.1 | 7.83.0 | 7.82.0 | 7.81.0 | 7.80.0 | 7.79.1 | 7.79.0 | 7.78.0 | 7.77.0 | 7.76.1 | 7.76.0 | 7.75.0 | 7.74.0 | 7.73.0 | 7.72.0 | 7.71.1 | 7.71.0 | 7.70.0 | 7.69.1 | 7.69.0 | 7.68.0 | 7.67.0 | 7.66.0 | 7.65.3 | 7.65.2 | 7.65.1 | 7.65.0 | 7.64.1 | 7.64.0 | 7.63.0 | 7.62.0 | 7.61.1 | 7.61.0 | 7.60.0 | 7.59.0 | 7.58.0 | 7.57.0 | 7.56.1 | 7.56.0 | 7.55.1 | 7.55.0 | 7.54.1 | 7.54.0 | 7.53.1 | 7.53.0 | 7.52.1 | 7.52.0 | 7.51.0 | 7.50.3 | 7.50.2 | 7.50.1 | 7.50.0 | 7.49.1 | 7.49.0 | 7.48.0 | 7.47.1 | 7.47.0 | 7.46.0 | 7.45.0 | 7.44.0 | 7.43.0
Debian1 product
  • curlAll versions (No fix recorded) | < 8.21.0~rc2-1
Haxx1 product
  • curl≥ 7.46.0, < 8.20.0
Ubuntu1 product
  • curl< 7.58.0-2ubuntu3.24+esm9 | < 7.68.0-1ubuntu2.25+esm4 | < 7.81.0-1ubuntu1.25 | < 8.5.0-2ubuntu10.10 | < 8.14.1-2ubuntu1.4 | < 8.18.0-1ubuntu2.2
Wolfi1 product
  • libcurl4All versions (No fix recorded)

7 vendors · 17 products

References

11 links
Show all 11 references