October 13, 2026

CVE Watchtower

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CVE-2026-8927NVD

Vulnerability Summary

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`.
Severity Level
CRITICAL(9.1)
Published Date
Jul 3, 2026
Last Modified
Jul 7, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
0.44%Probability
Root Weakness (CWE)
CWE-294: Unknown/Unlisted Weakness ↗
Refer to the official MITRE database for detailed architectural specifications regarding this weakness.
CVSS v3.1 Base Metrics — Score 9.1 (CRITICAL)
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityNone

Affected & Patched Versions

Affected Versions
  • Haxx Curl >= 7.12.0 and < 8.21.0
Patched Versions
  • Haxx Curl 8.21.0
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📈EPSS Spike Alerts — Catch rising risk before it peaks.
🎯Custom EPSS/CVSS — Filter noise, focus on risk.
🛡️Exploit Intel — A 2nd confirmed-exploit signal beyond KEV.
🐙GitHub Issues — Auto-tracked, no duplicates.
📬Weekly Digest — One clean summary, not inbox spam.
🏷️Watchlist Groups — Tag alerts by team (Infra/AppSec/SOC).
💬Webhooks — Slack & Teams integration.
🔀Smart Routing — Critical alerts to one channel, rest to another.
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External References