vulnerability / NVI-00005815 / Revision 2
Guzzle: Unbounded response cookies risk denial of service
OSV carries this publisher advisory for guzzlehttp/guzzle. This is an aggregated source copy; consult the original publisher and compare update dates.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
0.418%
FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.36142. Missing scores are unknown.
As of · FIRST EPSS
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
guzzlehttp/guzzle
source listedECOSYSTEM: introduced 0; fixed 7.15.1
### Impact In affected versions, Guzzle's built-in `CookieJar` accepts any number of `Set-Cookie` header fields from one response, with no limit on the size of each field. When a later request matches the stored cookies, Guzzle places every match into one generated `Cookie` header without limiting the number of cookies or the total header length. A malicious or compromised server can therefore return many large cookies, causing Guzzle to store attacker-controlled data in memory and copy it into later request headers. This can increase memory use and processing time. It can also make later requests fail when the generated header exceeds a limit in a handler, HTTP implementation, proxy, or destination server. A server on one sibling host, such as `attacker.example.com`, can also set parent-domain cookies that are later selected for another sibling, such as `service.example.com`. The denial can therefore affect a different service that uses the same jar. An application is affected when it enables the built-in cookie support, receives an attacker-controlled response, and retains or reuses the jar. The issue affects both built-in handlers because Guzzle manages these cookies itself i
03 / Response
What to do next
- vendor patch
The original advisory lists fixed boundaries 7.15.1 for guzzlehttp/guzzle. Confirm the publisher’s latest guidance.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database via OSV
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. FIRST EPSS
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-f283-ghqc-fg79 ↗
GitHub Advisory Database via OSV · vendor advisory
Observed . GitHub-origin advisory, CC-BY-4.0; OSV is an aggregate copy, not independent corroboration.
- CVE-2026-67353 ↗
FIRST EPSS · official catalog
Observed . FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 2 ·
Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.