CVE-2026-28435

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 65% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, cpp-httplib (httplib.h) does not enforce Server::set_payload_max_length() on the decompressed request body when using HandlerWithContentReader (streaming ContentReader) with Content-Encoding: gzip (or other supported encodings). A small compressed payload can expand beyond the configured payload limit and be processed by the application, enabling a payload size limit bypass and potential denial of service (CPU/memory exhaustion). This vulnerability is fixed in 0.35.0.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
38(Track)
EG Risk 38/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
36%
KEV
Not listed

Published

March 4, 2026

Last Modified

June 17, 2026

Advisory Details (2)

Auto-updated Aug 2, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github.
github Patch Available🟡 PoC Available

Payload size limit bypass via gzip decompression in ContentReader (streaming) allows oversized request bodies in cpp-httplib · Advisory · yhirose/cpp-httplib · GitHub

https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-xvfx-w463-6fpp
github_commit Patch Available

commit c99d7472b5cf (yhirose/cpp-httplib)

Patch available: yhirose/cpp-httplib v0.35.0 (contains commit c99d7472b5cf)

https://github.com/yhirose/cpp-httplib/commit/c99d7472b5cf4869d3897b9afc9792063a3d15a8

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
cpp-httplib0.11.4+ds-1 ... 0.41.0+ds-3~bpo13+1 (27 versions)——
Debian:13(1)
PackageVulnerable rangeFixed inDependents
cpp-httplib0.18.7-1 ... 0.41.0+ds-3~bpo13+1 (9 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
cpp-httplib0.18.7-1 ... 0.41.0+ds-3~bpo13+1 (7 versions)0.41.0+ds-3—

Weakness Classification(2)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 31× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 13:02 UTCOSV refresh
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 19:27 UTCEPSS rescore
  4. 2026-09-17 19:30 UTCEPSS rescore
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-16 05:15 UTCEPSS rescore
  7. 2026-09-13 16:47 UTCEPSS rescore
  8. 2026-09-12 15:01 UTCEPSS rescore
  9. 2026-09-11 14:52 UTCEPSS rescore
  10. 2026-09-10 09:34 UTCEPSS rescore
  11. 2026-09-08 22:00 UTCEPSS rescore
  12. 2026-09-07 16:01 UTCEPSS rescore
  13. 2026-09-06 13:47 UTCEPSS rescore
  14. 2026-09-06 13:47 UTCEPSS rescore
  15. 2026-09-04 05:06 UTCEPSS rescore
  16. 2026-09-02 14:11 UTCEPSS rescore
  17. 2026-09-01 13:53 UTCEPSS rescore
  18. 2026-09-01 04:39 UTCEPSS rescore
  19. 2026-09-01 04:39 UTCEPSS rescore
  20. 2026-08-31 17:04 UTCOSV refresh
  21. 2026-08-30 19:17 UTCEPSS rescore
  22. 2026-08-30 01:22 UTCEPSS rescore
  23. 2026-08-28 21:41 UTCEPSS rescore
  24. 2026-08-27 14:25 UTCEPSS rescore
  25. 2026-08-26 14:46 UTCEPSS rescore
Show 38 more
  1. 2026-08-25 13:49 UTCEPSS rescore
  2. 2026-08-24 14:17 UTCEPSS rescore
  3. 2026-08-23 00:19 UTCEPSS rescore
  4. 2026-08-21 23:49 UTCEPSS rescore
  5. 2026-08-20 22:55 UTCEPSS rescore
  6. 2026-08-20 22:55 UTCEPSS rescore
  7. 2026-08-19 17:03 UTCEPSS rescore
  8. 2026-08-18 13:48 UTCEPSS rescore
  9. 2026-08-17 13:47 UTCEPSS rescore
  10. 2026-08-16 14:56 UTCEPSS rescore
  11. 2026-08-16 02:14 UTCEPSS rescore
  12. 2026-08-15 01:30 UTCEPSS rescore
  13. 2026-08-14 08:33 UTCEG score recompute
  14. 2026-08-13 22:00 UTCEPSS rescore
  15. 2026-08-13 00:15 UTCEG score recompute
  16. 2026-08-12 13:50 UTCEPSS rescore
  17. 2026-08-11 23:14 UTCEG score recompute
  18. 2026-08-11 13:42 UTCEPSS rescore
  19. 2026-08-11 05:47 UTCEG score recompute
  20. 2026-08-11 00:00 UTCEPSS rescore
  21. 2026-08-09 21:03 UTCEG score recompute
  22. 2026-08-09 13:46 UTCEPSS rescore
  23. 2026-08-09 08:11 UTCEG score recompute
  24. 2026-08-08 16:37 UTCEPSS rescore
  25. 2026-08-07 20:02 UTCEG score recompute
  26. 2026-08-06 13:46 UTCEPSS rescore
  27. 2026-08-06 02:40 UTCEG score recompute
  28. 2026-08-05 19:17 UTCEPSS rescore
  29. 2026-08-04 15:10 UTCEPSS rescore
  30. 2026-08-04 02:34 UTCEG score recompute
  31. 2026-08-03 10:36 UTCEPSS rescore
  32. 2026-08-02 18:57 UTCEG score recompute
  33. 2026-08-02 02:26 UTCEPSS rescore
  34. 2026-08-01 04:16 UTCEPSS rescore
  35. 2026-07-30 16:27 UTCEPSS rescore
  36. 2026-07-30 01:30 UTCEPSS rescore
  37. 2026-07-28 15:36 UTCEPSS rescore
  38. 2026-07-27 13:52 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-28435?
CVE-2026-28435 is a high vulnerability published on March 4, 2026. cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to 0.35.0, cpp-httplib (httplib.h) does not enforce Server::setpayloadmax_length() on the decompressed request body when using HandlerWithContentReader (streaming ContentReader) with Content-Encoding: gzip (or…
When was CVE-2026-28435 disclosed?
CVE-2026-28435 was first published in the National Vulnerability Database on March 4, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-28435 actively exploited?
CVE-2026-28435 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 64.2% of all scored CVEs.
What is the CVSS score of CVE-2026-28435?
CVE-2026-28435 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-28435?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-28435, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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