Allocation of resources without limits or throttling in the HTTP/2 HPACK decoder in Apache HttpComponents Core (5.4.2 and earlier, 5.5-beta1 and earlier) allows an remote attacker to cause a denial of service through memory exhaustion by sending oversized compressed header blocks before the HTTP/2 SETTINGS acknowledgement causes the configured header list size limit to be applied.
CVE-2026-54428
Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-01. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 7.5; sources differ by 0.0.
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(high)
- EPSS
- 32.9%
- KEV
- Not listed
Published
July 1, 2026
Last Modified
July 6, 2026
Advisory Details (2)
Auto-updated Jul 1, 2026oss-security - CVE-2026-54428: Apache HttpComponents Core: HPackDecoder Unlimited Header List Size Before SETTINGS ACK
http://www.openwall.com/lists/oss-security/2026/07/01/3Vendor Advisories for CVE-2026-54428(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 21× in last 7d / 21× 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.
- 2026-07-07 01:43 UTCEG score recompute
- 2026-07-07 01:43 UTCGHSA enrichment
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 13:04 UTCEG score recompute
- 2026-07-06 13:03 UTCGHSA enrichment
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-06 00:24 UTCEG score recompute
- 2026-07-06 00:24 UTCGHSA enrichment
- 2026-07-05 11:44 UTCEG score recompute
- 2026-07-05 11:44 UTCGHSA enrichment
- 2026-07-05 02:31 UTCEPSS rescore
- 2026-07-05 02:30 UTCEPSS rescore
- 2026-07-04 23:06 UTCEG score recompute▲ 7.50
- 2026-07-04 23:05 UTCGHSA enrichment
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-04 06:31 UTCEPSS rescore
- 2026-07-01 21:08 UTCNVD updateCVSS v3 → 7.5 · severity → HIGH
- 2026-07-01 19:03 UTCEG score recompute
- 2026-07-01 19:03 UTCGHSA enrichment
Related CVEs(same CWE)
Same CWE
10 shownCWE-400
Frequently asked(5)
What is CVE-2026-54428?
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Dependency Blast Radius
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