CVE-2026-55851

ADVISORY - github

Summary

The HAProxyMessageDecoder in netty's codec-haproxy module performs protocol version detection by reading the 13th byte of the inbound stream as a signed Java byte and widening it to int without masking. When an attacker sends a PROXY protocol v2 binary prefix (0D 0A 0D 0A 00 0D 0A 51 55 49 54 0A) followed by version byte 0xFF, the sign extension produces -1, which collides with the decoder's "need more data" sentinel value. This collision traps the decoder in a version-detection loop where it perpetually requests more data without consuming any bytes, never instantiates the HeaderExtractor that enforces header size limits, and causes ByteToMessageDecoder to accumulate all subsequent inbound bytes into an unbounded cumulation buffer until the JVM exhausts its direct memory allocation.

EPSS Score⁠: 0.00612 (0.468)

Common Weakness Enumeration (CWE)

ADVISORY - github

CWE-400⁠

Uncontrolled Resource Consumption

Impacted images

Advisories

GitHub

CREATED

1 month ago

UPDATED

1 month ago

ADVISORY IDGHSA-q6cq-mhr2-jmr5⁠

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)

CWE-400⁠

CVSS SCORE

8.7high

Debian

CREATED

1 month ago

UPDATED

10 days ago

ADVISORY IDCVE-2026-55851⁠

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

Ubuntu

CREATED

1 month ago

UPDATED

25 days ago

ADVISORY IDCVE-2026-55851⁠

EXPLOITABILITY SCORE

3.9

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

CVSS SCORE

7.5medium

Chainguard

CREATED

7 days ago

UPDATED

7 days ago

ADVISORY ID

CGA-m5cw-3746-g39j

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

3 days ago

UPDATED

3 days ago

ADVISORY ID

MINI-247v-77rf-66vc

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

7 days ago

UPDATED

7 days ago

ADVISORY ID

MINI-25f6-jpfg-626c

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

24 days ago

UPDATED

24 days ago

ADVISORY ID

MINI-264p-39rc-5xgg

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

11 days ago

UPDATED

11 days ago

ADVISORY ID

MINI-2hrw-cg64-69g9

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

26 days ago

UPDATED

26 days ago

ADVISORY ID

MINI-3848-h9v9-j75w

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

17 days ago

UPDATED

17 days ago

ADVISORY ID

MINI-44h5-g63x-69r7

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

24 days ago

UPDATED

24 days ago

ADVISORY ID

MINI-46jj-933w-p45p

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

28 days ago

UPDATED

28 days ago

ADVISORY ID

MINI-4ghm-4jrj-ffr7

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

26 days ago

UPDATED

26 days ago

ADVISORY ID

MINI-54r6-qx6v-m9vf

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

25 days ago

UPDATED

25 days ago

ADVISORY ID

MINI-5r8j-4r44-cvfx

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

1 month ago

UPDATED

1 month ago

ADVISORY ID

MINI-69rh-2w2j-59f9

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

11 days ago

UPDATED

11 days ago

ADVISORY ID

MINI-92gf-c8jh-fmhg

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

2 days ago

UPDATED

2 days ago

ADVISORY ID

MINI-94rx-fx6j-cgm2

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

1 month ago

UPDATED

1 month ago

ADVISORY ID

MINI-9826-jh63-c37h

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

11 hours ago

UPDATED

11 hours ago

ADVISORY ID

MINI-9fpr-jphw-67cw

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

26 days ago

UPDATED

26 days ago

ADVISORY ID

MINI-9wph-2f6w-fpr8

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

9 days ago

UPDATED

9 days ago

ADVISORY ID

MINI-c768-h68f-jfrh

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

11 days ago

UPDATED

11 days ago

ADVISORY ID

MINI-ggmf-7jf4-qx32

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

30 days ago

UPDATED

30 days ago

ADVISORY ID

MINI-h5r8-qxg6-qxmf

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

28 days ago

UPDATED

28 days ago

ADVISORY ID

MINI-hjh2-7jq2-4wfc

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

25 days ago

UPDATED

25 days ago

ADVISORY ID

MINI-hm9p-4whm-f4x7

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

25 days ago

UPDATED

25 days ago

ADVISORY ID

MINI-jf4v-gh76-cq4g

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

23 days ago

UPDATED

23 days ago

ADVISORY ID

MINI-jjpq-7r4x-56xf

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

27 days ago

UPDATED

27 days ago

ADVISORY ID

MINI-jmff-hcfq-j39m

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

1 month ago

UPDATED

1 month ago

ADVISORY ID

MINI-mwvp-7936-vq46

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

23 days ago

UPDATED

23 days ago

ADVISORY ID

MINI-qqq3-r64v-34cr

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

24 days ago

UPDATED

24 days ago

ADVISORY ID

MINI-r4qf-f625-46xc

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

23 days ago

UPDATED

23 days ago

ADVISORY ID

MINI-r576-88xf-33pj

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

30 days ago

UPDATED

30 days ago

ADVISORY ID

MINI-r6gq-f355-h5cr

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

9 days ago

UPDATED

9 days ago

ADVISORY ID

MINI-r77j-5w7h-p497

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

1 month ago

UPDATED

1 month ago

ADVISORY ID

MINI-rq8w-6ww5-m738

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

17 hours ago

UPDATED

17 hours ago

ADVISORY ID

MINI-vfww-pf45-5857

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

3 days ago

UPDATED

3 days ago

ADVISORY ID

MINI-w245-4g5h-4wcf

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

25 days ago

UPDATED

25 days ago

ADVISORY ID

MINI-w4wq-29mc-g3qq

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

24 days ago

UPDATED

24 days ago

ADVISORY ID

MINI-w6pq-vv7j-m5g6

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

3 days ago

UPDATED

3 days ago

ADVISORY ID

MINI-wxjh-65gp-544j

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

26 days ago

UPDATED

26 days ago

ADVISORY ID

MINI-x745-5537-wp8h

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY

minimos

CREATED

23 days ago

UPDATED

23 days ago

ADVISORY ID

MINI-xfrr-g99w-v58r

EXPLOITABILITY SCORE

EXPLOITS FOUND

COMMON WEAKNESS ENUMERATION (CWE)-

RATING UNAVAILABLE FROM ADVISORY