Baitaphish
Security intelligence
SearchLatest briefing
CVE Explorer

CVE-2026-55953

The Erlang/OTP ssl TLS 1.2 (and earlier) and DTLS client does not verify that the cipher suite selected by the server in ServerHello was among the suites offered by the client in ClientHello. The client-side tls_handshake:hello/5 handler validates the negotiated protocol version and the downgrade sentinel but hands the server-chosen suite directly to ssl_handshake:handle_server_hello_extensions/9, which installs it without a membership check. The TLS 1.3 client path performs this check (per RFC
Lifecycle PUBLISHED1 preserved revisionFact urn:baitaphish:canonical-cve-fact-revision:v2:ab0aafa9e236c96c92a91219c80f88b18fd515a0e127e3fc53e2089805311d74
Known exploited
Not asserted
Disputed
No
Stale source
No
Conflicts
1

Preserved source conflicts

No provider value was silently selected as the winner.

affected · 3 assertions

{"cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["tls_handshake","ssl_handshake","ssl"],"packageName":"otp","packageURL":"pkg:sid/erlang.org/otp","product":"OTP","programFiles":["lib/ssl/src/tls_handshake.erl","lib/ssl/src/ssl_handshake.erl","lib/ssl/src/ssl.erl"],"programRoutines":[{"name":"tls_handshake:hello/5"},{"name":"ssl_handshake:handle_server_hello_extensions/9"},{"name":"ssl:connect/2"},{"name":"ssl:connect/3"},{"name":"ssl:connect/4"}],"vendor":"Erlang","versions":[{"lessThan":"R13B03","status":"unknown","version":"0","versionType":"o…

  • cve_program_cvelist_v5affected
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/affected/0

{"cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["tls_handshake","ssl_handshake","ssl"],"packageName":"ssl","packageURL":"pkg:otp/ssl?repository_url=https:%2F%2Fgithub.com%2Ferlang%2Fotp&vcs_url=git%20https:%2F%2Fgithub.com%2Ferlang%2Fotp.git","product":"OTP","programFiles":["src/tls_handshake.erl","src/ssl_handshake.erl","src/ssl.erl"],"programRoutines":[{"name":"tls_handshake:hello/5"},{"name":"ssl_handshake:handle_server_hello_extensions/9"},{"name":"ssl:connect/2"},{"name":"ssl:connect/3"},{"name":"ssl:connect/4"}],"repo":"https://github.com…

  • cve_program_cvelist_v5affected
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/affected/1

{"collectionURL":"https://github.com","cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["tls_handshake","ssl_handshake","ssl"],"packageName":"erlang/otp","packageURL":"pkg:github/erlang/otp","product":"OTP","programFiles":["lib/ssl/src/tls_handshake.erl","lib/ssl/src/ssl_handshake.erl","lib/ssl/src/ssl.erl"],"programRoutines":[{"name":"tls_handshake:hello/5"},{"name":"ssl_handshake:handle_server_hello_extensions/9"},{"name":"ssl:connect/2"},{"name":"ssl:connect/3"},{"name":"ssl:connect/4"}],"repo":"https://github.com/erlang/otp","vendor":"Erlang",…

  • cve_program_cvelist_v5affected
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/affected/2

Affected products and versions

3 source assertions
{"cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["tls_handshake","ssl_handshake","ssl"],"packageName":"otp","packageURL":"pkg:sid/erlang.org/otp","product":"OTP","programFiles":["lib/ssl/src/tls_handshake.erl","lib/ssl/src/ssl_handshake.erl","lib/ssl/src/ssl.erl"],"programRoutines":[{"name":"tls_handshake:hello/5"},{"name":"ssl_handshake:handle_server_hello_extensions/9"},{"name":"ssl:connect/2"},{"name":"ssl:connect/3"},{"name":"ssl:connect/4"}],"vendor":"Erlang","versions":[{"lessThan":"R13B03","status":"unknown","version":"0","versionType":"o…
  • cve_program_cvelist_v5affected
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/affected/0
{"cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["tls_handshake","ssl_handshake","ssl"],"packageName":"ssl","packageURL":"pkg:otp/ssl?repository_url=https:%2F%2Fgithub.com%2Ferlang%2Fotp&vcs_url=git%20https:%2F%2Fgithub.com%2Ferlang%2Fotp.git","product":"OTP","programFiles":["src/tls_handshake.erl","src/ssl_handshake.erl","src/ssl.erl"],"programRoutines":[{"name":"tls_handshake:hello/5"},{"name":"ssl_handshake:handle_server_hello_extensions/9"},{"name":"ssl:connect/2"},{"name":"ssl:connect/3"},{"name":"ssl:connect/4"}],"repo":"https://github.com…
  • cve_program_cvelist_v5affected
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/affected/1
{"collectionURL":"https://github.com","cpes":["cpe:2.3:a:erlang:erlang\\/otp:*:*:*:*:*:*:*:*"],"defaultStatus":"unaffected","modules":["tls_handshake","ssl_handshake","ssl"],"packageName":"erlang/otp","packageURL":"pkg:github/erlang/otp","product":"OTP","programFiles":["lib/ssl/src/tls_handshake.erl","lib/ssl/src/ssl_handshake.erl","lib/ssl/src/ssl.erl"],"programRoutines":[{"name":"tls_handshake:hello/5"},{"name":"ssl_handshake:handle_server_hello_extensions/9"},{"name":"ssl:connect/2"},{"name":"ssl:connect/3"},{"name":"ssl:connect/4"}],"repo":"https://github.com/erlang/otp","vendor":"Erlang",…
  • cve_program_cvelist_v5affected
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/affected/2

Provider-owned CVSS observations

1 source assertion
{"metric":{"Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","Safety":"NOT_DEFINED","attackComplexity":"LOW","attackRequirements":"PRESENT","attackVector":"NETWORK","baseScore":9.1,"baseSeverity":"CRITICAL","privilegesRequired":"NONE","providerUrgency":"NOT_DEFINED","subAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","userInteraction":"NONE","valueDensity":"NOT_DEFINED","vectorString":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N","version":"4.0","vulnAvailabilityImpact":"NONE","vulnConfidentialityImpact":"HIGH","vulnIntegrityImpac…
  • cve_program_cvelist_v5cvss
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/metrics/0/cvssV4_0

CWE assertions

1 source assertion
{"cweId":"CWE-757","description":"CWE-757 Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')","lang":"en","type":"CWE"}
  • cve_program_cvelist_v5cwe
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/problemTypes/0/descriptions/0

Source references

7 source assertions
{"tags":["related"],"url":"https://cna.erlef.org/cves/CVE-2026-55953.html"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/references/1
{"tags":["patch"],"url":"https://github.com/erlang/otp/commit/064e236414614f9085cbbbd6eacf0e43c02d1b4b"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/references/4
{"tags":["patch"],"url":"https://github.com/erlang/otp/commit/0a82596d425abe43dc2e0b3d74aa1557ef74051c"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/references/5
{"tags":["patch"],"url":"https://github.com/erlang/otp/commit/e6ff938116b2872bccc478af7fefb56627285b77"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/references/6
{"tags":["vendor-advisory","related"],"url":"https://github.com/erlang/otp/security/advisories/GHSA-c6cw-pr89-w882"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/references/0
{"tags":["related"],"url":"https://osv.dev/vulnerability/EEF-CVE-2026-55953"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/references/2
{"tags":["x_version-scheme"],"url":"https://www.erlang.org/doc/system/versions.html#order-of-versions"}
  • cve_program_cvelist_v5reference
    urn:baitaphish:normalized-source-record:v2:9afa14255c09f5edfe7f013af4aa0f9ea1eb1953b9075b6bce24fc5bda99f95b · sha256:e0ec136d7ebe4468… · /containers/cna/references/3

Attribution and limitations

  • CVE Program CVEList V5: Reproduce the MITRE copyright designation and CVE license in copies. Source →

Provider severity values are preserved separately. Baitaphish does not convert them into a risk rating, infer affected products, or treat EPSS as observed exploitation.

← Back to CVE Explorer