CVE-2026-8927 — env-set cross-proxy Digest auth state leak

Description (CNA)

When reusing a libcurl handle for sequential transfers driven by environment-variable proxy configuration, libcurl fails to clear the proxy authentication state between requests. Specifically, if the initial transfer authenticates against `proxyA` using Digest auth, a subsequent transfer routed through `proxyB` erroneously leaks the `Proxy-Authorization:` header intended solely for `proxyA`.

Affected (CNA)

Vendor / product	Versions
curl / curl	affected 7.12.0 before 8.14.2; affected 8.15.0 before 8.16.1; affected 8.17.0 before 8.20.1
curl / curl	affected fc6eff13b5414caf6edf22d73a3239e074a04216 before 5c225384b8d52c67ce8259c6e4203bc57aacb567
curl / curl	affected 8.20.0; affected 8.19.0; affected 8.18.0; affected 8.17.0; affected 8.16.0; affected 8.15.0; affected 8.14.1; affected 8.14.0; affected 8.13.0; affected 8.12.1; affected 8.12.0; affected 8.11.1; affected 8.11.0; affected 8.10.1; affected 8.10.0; affected 8.9.1; affected 8.9.0; affected 8.8.0; affected 8.7.1; affected 8.7.0; affected 8.6.0; affected 8.5.0; affected 8.4.0; affected 8.3.0; affected 8.2.1; affected 8.2.0; affected 8.1.2; affected 8.1.1; affected 8.1.0; affected 8.0.1; affected 8.0.0; affected 7.88.1; affected 7.88.0; affected 7.87.0; affected 7.86.0; affected 7.85.0; affected 7.84.0; affected 7.83.1; affected 7.83.0; affected 7.82.0; affected 7.81.0; affected 7.80.0; affected 7.79.1; affected 7.79.0; affected 7.78.0; affected 7.77.0; affected 7.76.1; affected 7.76.0; affected 7.75.0; affected 7.74.0; affected 7.73.0; affected 7.72.0; affected 7.71.1; affected 7.71.0; affected 7.70.0; affected 7.69.1; affected 7.69.0; affected 7.68.0; affected 7.67.0; affected 7.66.0; affected 7.65.3; affected 7.65.2; affected 7.65.1; affected 7.65.0; affected 7.64.1; affected 7.64.0; affected 7.63.0; affected 7.62.0; affected 7.61.1; affected 7.61.0; affected 7.60.0; affected 7.59.0; affected 7.58.0; affected 7.57.0; affected 7.56.1; affected 7.56.0; affected 7.55.1; affected 7.55.0; affected 7.54.1; affected 7.54.0; affected 7.53.1; affected 7.53.0; affected 7.52.1; affected 7.52.0; affected 7.51.0; affected 7.50.3; affected 7.50.2; affected 7.50.1; affected 7.50.0; affected 7.49.1; affected 7.49.0; affected 7.48.0; affected 7.47.1; affected 7.47.0; affected 7.46.0; affected 7.45.0; affected 7.44.0; affected 7.43.0; affected 7.42.1; affected 7.42.0; affected 7.41.0; affected 7.40.0; affected 7.39.0; affected 7.38.0; affected 7.37.1; affected 7.37.0; affected 7.36.0; affected 7.35.0; affected 7.34.0; affected 7.33.0; affected 7.32.0; affected 7.31.0; affected 7.30.0; affected 7.29.0; affected 7.28.1; affected 7.28.0; affected 7.27.0; affected 7.26.0; affected 7.25.0; affected 7.24.0; affected 7.23.1; affected 7.23.0; affected 7.22.0; affected 7.21.7; affected 7.21.6; affected 7.21.5; affected 7.21.4; affected 7.21.3; affected 7.21.2; affected 7.21.1; affected 7.21.0; affected 7.20.1; affected 7.20.0; affected 7.19.7; affected 7.19.6; affected 7.19.5; affected 7.19.4; affected 7.19.3; affected 7.19.2; affected 7.19.1; affected 7.19.0; affected 7.18.2; affected 7.18.1; affected 7.18.0; affected 7.17.1; affected 7.17.0; affected 7.16.4; affected 7.16.3; affected 7.16.2; affected 7.16.1; affected 7.16.0; affected 7.15.5; affected 7.15.4; affected 7.15.3; affected 7.15.2; affected 7.15.1; affected 7.15.0; affected 7.14.1; affected 7.14.0; affected 7.13.2; affected 7.13.1; affected 7.13.0; affected 7.12.3; affected 7.12.2; affected 7.12.1; affected 7.12.0

CWE

CWE-294

References

ADP enrichment

CISA-ADP

No English description supplied.

https://hackerone.com/reports/3744543