Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
5 results
Apr 9, 2026osslsigncode is a tool that implements Authenticode signing and timestamping.CVE-2026-39856 · Other software · mtrojnar · reported by GitHubMedium 5.5
osslsigncode is a tool that implements Authenticode signing and timestamping. Prior to 2.13, an out-of-bounds read vulnerability exists in osslsigncode version 2.12 and earlier in the PE page-hash computation code (pe_page_hash_calc()). When processing PE sections for page hashing, the function uses PointerToRawData and SizeOfRawData values from section headers without validating that the referenced region lies within the mapped file. An attacker can craft a PE file with section headers that point beyond the end of the file. When osslsigncode computes page hashes for such a file, it may attempt to hash data from an invalid memory region, causing an out-of-bounds read and potentially crashing the process. The vulnerability can be triggered while signing a malicious PE file with page hashing enabled (-ph), or while verifying a malicious signed PE file that already contains page hashes. Verification of an already signed file does not require the verifier to pass -ph. This vulnerability is fixed in 2.13.
- Product
- osslsigncode
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 9, 2026osslsigncode is a tool that implements Authenticode signing and timestamping.CVE-2026-39855 · Other software · mtrojnar · reported by GitHubMedium 5.5
osslsigncode is a tool that implements Authenticode signing and timestamping. Prior to 2.13, an integer underflow vulnerability exists in osslsigncode version 2.12 and earlier in the PE page-hash computation code (pe_page_hash_calc()). When page hash processing is performed on a PE file, the function subtracts hdrsize from pagesize without first validating that pagesize >= hdrsize. If a malicious PE file sets SizeOfHeaders (hdrsize) larger than SectionAlignment (pagesize), the subtraction underflows and produces a very large unsigned length. The code allocates a zero-filled buffer of pagesize bytes and then attempts to hash pagesize - hdrsize bytes from that buffer. After the underflow, this results in an out-of-bounds read from the heap and can crash the process. The vulnerability can be triggered while signing a malicious PE file with page hashing enabled (-ph), or while verifying a malicious signed PE file that already contains page hashes. Verification of an already signed file does not require the verifier to pass -ph. This vulnerability is fixed in 2.13.
- Product
- osslsigncode
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 9, 2026osslsigncode is a tool that implements Authenticode signing and timestamping.CVE-2026-39853 · Other software · mtrojnar · reported by GitHubHigh 7.8
osslsigncode is a tool that implements Authenticode signing and timestamping. Prior to 2.12, A stack buffer overflow vulnerability exists in osslsigncode in several signature verification paths. During verification of a PKCS#7 signature, the code copies the digest value from a parsed SpcIndirectDataContent structure into a fixed-size stack buffer (mdbuf[EVP_MAX_MD_SIZE], 64 bytes) without validating that the source length fits within the destination buffer. This pattern is present in the verification handlers for PE, MSI, CAB, and script files. An attacker can craft a malicious signed file with an oversized digest field in SpcIndirectDataContent. When a user verifies such a file with osslsigncode verify, the unbounded memcpy can overflow the stack buffer and corrupt adjacent stack state. This vulnerability is fixed in 2.12.
- Product
- osslsigncode
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 25, 2026An issue in mtrojnar Osslsigncode affected at v2.10 and before allows a remote attacker to escalate privileges via the osslsigncode.c componentCVE-2025-70888 · Other software · Osslsigncode Project · reported by MITRECritical 9.8
An issue in mtrojnar Osslsigncode affected at v2.10 and before allows a remote attacker to escalate privileges via the osslsigncode.c component
- Product
- Osslsigncode
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 3, 2023Buffer Overflow vulnerability in mtrojnar osslsigncode v.2.3 and before allows a local attacker to execute arbitrary code via a crafted .exe, .sys, and .dll filCVE-2023-36377 · Other software · Osslsigncode Project · reported by MITREHigh 7.8
Buffer Overflow vulnerability in mtrojnar osslsigncode v.2.3 and before allows a local attacker to execute arbitrary code via a crafted .exe, .sys, and .dll files.
- Product
- Osslsigncode
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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