AsyncHttpClient: Digest mutual authentication is switched off by a peer offering qop=auth-int

published 2026-10-07 32 d ago modified 2026-10-08 31 d ago also EUVD-2026-94638

cvss: 8.8; version 4.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 29%
public exploits: 0; none known

The AsyncHttpClient (AHC) library allows Java applications to easily execute HTTP requests and asynchronously process HTTP responses. In 3.0.12, a peer offering only Digest qop=auth-int causes mutual-authentication verification to be skipped. AuthenticatorUtils.computeExpectedRspAuth returns no expected value for auth-int, and Interceptors treats that result as unverifiable but nonfatal, so a response with an invalid rspauth value is accepted. A peer that does not know the shared secret can therefore be accepted as the authenticated server. This issue is fixed in version 3.0.13.

Patch / fix

links 2

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-107279 updated 2026-10-31 cvss 8.2

org.asynchttpclient/async-http-client: AsyncHttpClient: Mutual authentication bypass via Digest auth-int negotiation

Red Hat Fuse 7 async-http-client 2.6.0
not affected: vulnerable code not in execute path

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 31 d ago (2026-10-08)

Exploit prediction

0.36% chance of exploitation in the next 30 days, higher than 29% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	8.8	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
CNA	4.0	8.8	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

AsyncHttpClient async-http-client

Classification

Weakness

CWE-303 Incorrect Implementation of Authentication Algorithm
CWE-757 Selection of Less-Secure Algorithm During Negotiation

References

Sources

CVE List CVE-2026-107279
NVD CVE-2026-107279

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Summary