{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","favicon":"https://feed.craftedsignal.io/favicon-32x32.png","feed_url":"https://feed.craftedsignal.io/products/go--1.27.3-/--1.26.10/feed.json","home_page_url":"https://feed.craftedsignal.io/","icon":"https://feed.craftedsignal.io/apple-touch-icon.png","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":6.8,"id":"CVE-2026-111943"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["certifi (\u003c 2026.10.19)","pip (\u003c 26.2.2)","Go (\u003c 1.27.3 / \u003c 1.26.10)","Node.js (\u003c 26.12.1 / \u003c 24.22.1 / \u003c 22.23.4)","Electron (\u003c 44.9.1 / \u003c 43.8.1 / \u003c 42.11.16)","rustls-webpki (\u003c 0.103.16)","webpki-roots (\u003c 1.0.10)","Bun (\u003c 1.4.4)","sigstore (\u003c 4.5.1)","ca-certificates","NSS (\u003c 3.131.1)","Java (cacerts)"],"_cs_severities":["critical"],"_cs_tags":[],"_cs_type":"advisory","_cs_vendors":["eMudhra","Python","Go","Node.js","Electron","Rust","Bun","Debian","Ubuntu","Alpine","Oracle","Apple","Microsoft","Google"],"content_html":"\u003cp\u003eEight eMudhra/emSign intermediate CA certificates created in April 2025 utilized P-384 ECC keys with trivially small private scalars (d in {4, 56, 66, 115, 155, 156, 230, 237}). Because these scalars are so small, the private key can be recovered from the public certificate in milliseconds. Six of the compromised intermediates could mint TLS certificates for any hostname, while two functioned as code-signing CAs. While major browsers (Chrome, Firefox, Safari) and OS vendors (Microsoft, Apple) have pushed blocks, non-browser software and environments relying on bundled or outdated CA trust stores remain vulnerable.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eRecovery: Attacker extracts the public key from an affected intermediate certificate and performs a brute-force search across the 8 known scalar candidates to derive the private key.\u003c/li\u003e\n\u003cli\u003eForgery: Attacker generates a new leaf key pair and signs a certificate for any target hostname (CN/SAN) using the recovered CA private key.\u003c/li\u003e\n\u003cli\u003eMITM Setup: Attacker deploys a TLS server configured with the forged certificate chain.\u003c/li\u003e\n\u003cli\u003eRedirection: Attacker forces victim traffic to the MITM server (e.g., via DNS poisoning or ARP spoofing).\u003c/li\u003e\n\u003cli\u003eInterception: Victim client connects; because the trust store is unpatched, it validates the forged certificate, allowing the attacker to decrypt and inspect all TLS traffic.\u003c/li\u003e\n\u003cli\u003ePost-exploitation: Attacker injects malicious payloads, steals credentials, or establishes persistent C2 channels via the compromised connection.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation allows for the interception of HTTPS traffic (MITM), deployment of trusted phishing sites for any domain, and the creation of valid-looking code-signing certificates to sign malware. All traffic protected by software using unpatched CA bundles or trust stores is subject to decryption.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpdate CA trust stores and cryptographic libraries immediately: Python certifi (2026.10.19+), pip (26.2.2+), Go (1.27.3/1.26.10+), and Node.js (22.23.4/24.22.1/26.12.1+).\u003c/li\u003e\n\u003cli\u003eAdd the 16 SHA-256 hashes of the compromised CA certificates to the \u003ccode\u003eblocked.certs\u003c/code\u003e list for all Java environments.\u003c/li\u003e\n\u003cli\u003eRebuild containers and binaries that bundle trust stores (e.g., Debian/Ubuntu/Alpine/RHEL-based images).\u003c/li\u003e\n\u003cli\u003eScan internal PKI and trust stores for the specific root certificate fingerprints listed in section 7 of the source.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-11-05T03:43:09Z","date_published":"2026-11-05T03:43:09Z","id":"https://feed.craftedsignal.io/briefs/2026-11-emudhra-ca-weakness/","summary":"Eight eMudhra/emSign intermediate CA certificates were generated with weak P-384 ECC private keys, allowing attackers to forge valid TLS and code-signing certificates and perform seamless Man-in-the-Middle attacks.","title":"eMudhra/emSign: Weak Intermediate CA Private Keys (CVE-2026-111943)","url":"https://feed.craftedsignal.io/briefs/2026-11-emudhra-ca-weakness/"}],"language":"en","title":"CraftedSignal Threat Feed - Go (\u003c 1.27.3 / \u003c 1.26.10)","version":"https://jsonfeed.org/version/1.1"}