Stack-based Buffer OverflowWeakness · CWE-121

CVE-2026-0719

HIGH · 8.6 CVSS v3.1 Published 2026-01-08

Mitigation only

No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.

See remediation →

95/100

Remediation priority · Urgent

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

A flaw was identified in the NTLM authentication handling of the libsoup HTTP library, used by GNOME and other applications for network communication. When processing extremely long passwords, an internal size calculation can overflow due to improper use of signed integers. This results in incorrect memory allocation on the stack, followed by unsafe memory copying. As a result, applications using libsoup may crash unexpectedly, creating a denial-of-service risk.

Technical summary

dbcve analysis · high confidence

The vulnerability exists in the NTLM authentication module of libsoup, an HTTP library used by GNOME applications. When processing extremely long passwords, a signed integer overflow occurs in an internal size calculation, causing the library to allocate an incorrectly sized buffer on the stack. This leads to unsafe memory copying and potential stack corruption, resulting in application crashes and denial of service.

MitigationApply the official libsoup security patch when available, which should correct the signed integer handling in NTLM authentication. As a temporary mitigation, avoid using extremely long passwords with affected applications until the library is updated.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown

From the vector

Attack vector: Network
Complexity: Low
Privileges: None
User interaction: None
Scope: Unchanged
Confidentiality: Low
Integrity: Low
Availability: High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H

Am I affected?

dbcve checks

Work through these to decide whether this CVE applies to you.

Identify installed libsoup version

Run 'pkg-config --modversion libsoup-3.0' or 'pkg-config --modversion libsoup-2.4' to check the installed libsoup version. On some systems, check '/usr/lib/pkgconfig/libsoup-3.0.pc' or similar for version details.

Affected if The installed version is unpatched and falls within the vulnerable range (prior to the fix for CVE-2026-0719). Compare against the fixed version in your distribution's security advisories.
Find applications or services using libsoup

Search for binaries or services that link against libsoup by running 'ldd' on suspected binaries or checking application dependencies. Look for GNOME-related HTTP clients, mail clients, or synchronization tools that use libsoup.

Affected if Any application linked against a vulnerable libsoup version that performs HTTP authentication.
Check for NTLM authentication usage

Inspect application configuration files, logs, or code for NTLM or 'NTLMSSP' authentication usage. Review proxy settings or HTTP client configurations where NTLM authentication might be enabled.

Affected if NTLM authentication is configured or could be triggered with the affected application, as the vulnerability specifically exists in libsoup's NTLM authentication handling.
Assess password handling exposure

Determine if the application or proxy using libsoup NTLM auth could receive or process long passwords from untrusted sources. Check input validation for password fields in the application's authentication flow.

Affected if User-supplied passwords can reach the libsoup NTLM authentication code without length validation, enabling the integer overflow trigger.

You are affected if you run any application using a vulnerable libsoup version with NTLM authentication enabled and untrusted or long passwords can be passed to the authentication handler.

Generated from the published advisory. Verify against your own configuration.

Remediation

From vendor data

Mitigation available No clean upgrade yet — mitigate in the meantime

Mitigation

Apply the official libsoup security patch when available, which should correct the signed integer handling in NTLM authentication. As a temporary mitigation, avoid using extremely long passwords with affected applications until the library is updated.

Have this fixed Scoped from the published advisory

Consultation6.0 h
Implementation12.0 h
Testing8.0 h
Review / QA4.0 h

30.0 hours of engineering $5,280

Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $8,448.

Scan for this in your stack

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References

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-0719 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2026-0719?

The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.

The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here

Verified mitigations, workarounds, and config changes
Version or environment caveats, and links to real fixes
No weaponised exploit code, or anything meant to cause harm
No spam, self-promotion, credentials, or personal data

At a glance

A fix existsA vendor remedy is published

Severity 8.6 High

Exploit likelihood EPSS, next 30 days 0.6%

Remediation

A high-priority fix

Have this fixed 30 hrs · Moderate

Typical engagement from $5,280

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2026-0719 and return a fixed quote and timeline.

You’ll deal with our team directly and deploy the reviewed fix to staging first — never straight to production.

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

Check your environment

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

Scan for this in your stack

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Practitioner notes

No notes yet

Official description

Technical summary

CVSS breakdown

Am I affected?

Remediation

References