SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-9079

libcurl had a flaw that when instructed to clear proxy authentication credentials which made it not do so, leaving the old credentials around to get used for subsequent transfers that should not know nor use them.

CRITICAL 9.8EPSS 1.06%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.06%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

libcurl had a flaw that when instructed to clear proxy authentication credentials which made it not do so, leaving the old credentials around to get used for subsequent transfers that should not know nor use them.

CVSS 3.1
9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.06% probability · 63th percentile
CISA KEV
Not listed
Weakness
CWE-522
Affected
haxx/curl
Source
2499f714-1537-4658-8207-48ae4bb9eae9

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.