CVE-2026-57487 — libupnp chunked HTTP bodies can bypass g_maxContentLength and be fully buffered
pupnp is an SDK for development of UPnP device and control point applications. Prior to 2.0.2, Transfer-Encoding: chunked causes the HTTP parser in upnp/src/genlib/net/http/httpparser.c to leave parser->content_length at zero while parser_parse_chunky_entity and parser_parse_chunky_body accumulate decoded bytes in parser->msg.entity. The g_maxContentLength checks in http_RecvMessage in upnp/src/genlib/net/http/httpreadwrite.c therefore reject oversized numeric Content-Length bodies but do not enforce the same limit on decoded chunked bodies. A remote peer that can reach a SOAP, GENA, miniserver, or control-point HTTP response path can make the process buffer an entity larger than the configured maximum, causing resource exhaustion and denial of service. This issue is fixed in 2.0.2.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Pupnp Pupnp).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes matching the vulnerability class (denial of service), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | security-advisories@github.com via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: security-advisories@github.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
CWE-770 · Allocation of Resources Without Limits or Throttling
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Track CPU/memory spikes and availability drops correlated with request patterns.
Timeline
What happened to this CVE, newest first.
- 2026
- Source status changed · Published → Awaiting Analysis
- Record published
- CVSS changed · 7.5
- Source status changed · → Published
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 16, 2026 – Oct 16, 2026
References
3 on the record
Elsewhere on this site
Related CVEs (same products)
- High CVE-2026-77630 pupnp: Denial of service via blocking DNS resolution in parse_uri()/GENA callback parsing 19h
- Medium CVE-2026-55862 pupnp: Incomplete fix for CVE-2021-28302: recursive DOM functions cause stack overflow 19h
- High CVE-2026-57486 pupnp: NULL pointer dereference in ixmlNode_compare crashes on non-namespaced attributes 19h
- High CVE-2026-57488 pupnp: Integer truncation in HTTP Content-Length parsing enables request smuggling 19h
- Medium CVE-2026-41682 pupnp: Port truncation via atoi() cast in parse_uri() allows SSRF port confusion May 8, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No FIRST EPSS score.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-57487 is "libupnp chunked HTTP bodies can bypass g_maxContentLength and be fully buffered", rated High. It affects Pupnp (Pupnp); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
Comments
Moderated technical discussion. Read the community guidelines.
No comments yet.
Sign in or create an account to comment and suggest corrections.