Vulnerability in Openssl (CVE-2023-3817)
Summary
Vulnerability in Openssl (CVE-2023-3817). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
Issue summary: Checking excessively long DH keys or parameters may be very slow.
Impact summary: Applications that use the functions DH_check(), DH_check_ex()
or EVP_PKEY_param_check() to check a DH key or DH parameters may experience long
delays. Where the key or parameters that are being checked have been obtained
from an untrusted source this may lead to a Denial of Service.
The function DH_check() performs various checks on DH parameters. After fixing
CVE-2023-3446 it was discovered that a large q parameter value can also trigger
an overly long computation during some of these checks. A correct q value,
if present, cannot be larger than the modulus p parameter, thus it is
unnecessary to perform these checks if q is larger than p.
An application that calls DH_check() and supplies a key or parameters obtained
from an untrusted source could be vulnerable to a Denial of Service attack.
The function DH_check() is itself called by a number of other OpenSSL functions.
An application calling any of those other functions may similarly be affected.
The other functions affected by this are DH_check_ex() and
EVP_PKEY_param_check().
Also vulnerable are the OpenSSL dhparam and pkeyparam command line applications
when using the "-check" option.
The OpenSSL SSL/TLS implementation is not affected by this issue.
The OpenSSL 3.0 and 3.1 FIPS providers are not affected by this issue.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2023-3817 has been found in Openssl.
Risk of unauthorized operations or information disclosure. CVSS score: 5.3/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Openssl CVE-2023-3817" on the vendor's site.
CVE-2023-3817 (Openssl) — CWE-606 / CVSS v3 5.3
Attack vector: remote (network-reachable) / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-606) exists in Openssl.
Check the vendor advisory for the affected versions of Openssl.
Severity: Medium (CVSS 5.3/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Openssl' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Openssl' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Opensslを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Alpine Linux ALPINE-CVE-2023-3817 openssl Fixed in: 1.1.1v-r0
- Debian DEBIAN-CVE-2023-3817 openssl Fixed in: 1.1.1v-0~deb11u1
- Ubuntu UBUNTU-CVE-2023-3817 openssl Fixed in: 1.0.2g-1ubuntu4.20+esm10
References
- patch git.openssl.org
- patch git.openssl.org
- patch git.openssl.org
- patch openssl.org
- web nvd.nist.gov
- web git.openssl.org
- web openwall.com
- web seclists.org
- web lists.debian.org
- web openwall.com
- web openwall.com
- web openwall.com
- web security.gentoo.org
- web security.netapp.com
- web security.netapp.com
- web security.netapp.com
- web cert-portal.siemens.com
- web cert-portal.siemens.com
- web cert-portal.siemens.com
- web cert-portal.siemens.com
- web github.com
- web security.netapp.com
- web security.netapp.com
- web security.netapp.com