ZDF
Sign inSign up

Vulnerabilities

Vulnerability · CVE-2026-6253

curl might erroneously pass on credentials for a first proxy to a second proxy.

Published May 13, 2026 · catalog updated Oct 18, 2026 · curl might erroneously pass

Check if you run it

No confirmed exploitation is on record for CVE-2026-6253. EPSS is 0.72%. Act only if a listed version of curl might erroneously pass is installed.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (curl might erroneously pass).
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Medium5.9
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.72%
Remediation
Advisory link
Affected products
Alpine:v3.21 curl · Alpine:v3.22 curl · Alpine:v3.23 curl · Alpine:v3.24 curl · cpe haxx/curl

curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. while using the first proxy (using say ), curl is asked to follow a redirect to a URL using another scheme (say ), accessed using a second, different, proxy

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • Alpine:v3.21 curl7.14.1 → 8.14.1-r3
  • Alpine:v3.22 curl7.14.1 → 8.14.1-r4
  • Alpine:v3.23 curl7.14.1 → 8.20.0-r0
  • Alpine:v3.24 curl7.14.1 → 8.20.0-r0
  • cpe haxx/curlversion unspecified

How to fix CVE-2026-6253

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-6253. EPSS is 0.72%. Act only if a listed version of curl might erroneously pass is installed.

Which versions are affected?

Compare what you have installed with 7.14.1 → 8.14.1-r3, 7.14.1 → 8.14.1-r4, 7.14.1 → 8.20.0-r0. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-522: Insufficiently Protected Credentials. EPSS 0.72%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. May 13, 2026 · NIST NVD

    Detected

    curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. while using the first proxy (using say ), curl is asked to follow a redirect to a URL using another scheme

  2. Sep 15, 2026 · NIST NVD

    Updated

    curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. while using the first proxy (using say ), curl is asked to follow a redirect to a URL using another scheme

  3. Oct 18, 2026 · Trivy Vulnerability DB

    Fix available

    curl fixed in 8.14.1-r3; curl fixed in 8.14.1-r4; curl fixed in 8.20.0-r0; curl fixed in 8.20.0-r0

  4. Oct 18, 2026 · Trivy Vulnerability DB

    Fix available

    curl fixed in 8.14.1-r3

  5. Oct 18, 2026 · Trivy Vulnerability DB

    Fix available

    curl fixed in 8.14.1-r4

  6. Oct 18, 2026 · Trivy Vulnerability DB

    Fix available

    curl fixed in 8.20.0-r0

  7. Oct 18, 2026 · Trivy Vulnerability DB

    Updated

    curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no credentials 4. while using the first proxy (using say ), curl is asked to follow a redirect to a URL using another scheme

Sources

  • CVE.orgVulnerability recordCVE-2026-6253

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-6253

    30-day exploitation probability 0.7%

    first.org
  • NIST NVDVulnerability recordCVE-2026-6253

    curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no

    nvd.nist.gov
  • Trivy Vulnerability DBPackage advisoryALPINE-CVE-2026-6253

    curl might erroneously pass on credentials for a first proxy to a second proxy. This can happen when the following conditions are true: 1. curl is setup to use specific different proxies for different URL schemes 2. the first proxy needs credentials 3. the second proxy uses no cr

    osv.dev

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.