CVE-2026-55011
Integer underflow (wrap or wraparound) in Microsoft Defender allows an unauthorized attacker to execute code locally.
CVSS
7.8
High
EPSS
0.4%
p31
KEV
—
Exploit Today
9
0-100
Published: Jul 14, 2026 · Last modified: Jul 24, 2026 · CWE-191
0.4%EPSS · 30 days0.4%
2026-08-232026-09-20
Integer underflow (wrap or wraparound) in Microsoft Defender allows an unauthorized attacker to execute code locally.
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2026-940906.3 MED—
———A security flaw has been discovered in JusticeRage Manalyze 1.0.0. The affected element is the function PE::_parse_debug of the file manape/pe.cpp of the component PE Parser. The manipulation of the argument misc.Length results in integer underflow. The attack may be performed from remote. The patch is identified as 3e299685759f4f767088871de58c5d07f98ee382. A patch should be applied to remediate this issue.8hCVE-2026-617206.2 MED4.0%
——1FluidSynth is a software synthesizer based on the SoundFont 2 specifications. From 2.5.0 until 2.5.6, the SF2 parser computes the DMOD modulator count as chunk.size / SF_MOD_SIZE - 1 without rejecting chunks smaller than one record. A crafted SF2 file containing a zero-sized DMOD chunk makes the unsigned subtraction wrap to UINT_MAX, and the parser then attempts billions of SFMod allocations. This exhausts process memory and causes denial of service. No workaround is available. This issue is fixed in version 2.5.6.2dCVE-2026-935997.5 HIG28.2%
——8rustls-webpki through 0.103.12 (and 0.104.0-alpha releases before 0.104.0-alpha.7) contains a reachable panic in bit_string_flags() in src/der.rs. The input guard fails to reject a named-bit BIT STRING whose content is exactly [0x00] (zero padding bits and no data bytes), so raw_bits.len() - 1 underflows on the empty slice and the subsequent index operation panics (subtract-with-overflow in debug, index-out-of-bounds in release). The condition is reachable through the public API BorrowedCertRevocationList::from_der() when a CRL contains an issuingDistributionPoint extension with such an onlySomeReasons value. Exploitation requires an application that explicitly opts in to CRL revocation checking by passing RevocationOptions to verify_for_usage() and that parses CRL bytes obtained from a source the attacker can influence; the default rustls configuration, which does not use RevocationOptions, is unaffected. A crafted CRL causes a denial of service via the panic. Fixed in 0.103.13 and 0.104.0-alpha.7.3dCVE-2026-933955.3 MED15.1%
——5A missing lower-bound validation in the bson_new_from_buffer() function of libbson allows an integer underflow when processing BSON data with a zero-length prefix. The function reads a 32-bit document length from the input buffer but does not verify that the value is at least 5 (the minimum valid BSON document size) before using it in an array index calculation. When the length field is zero, the expression used to check the document's null terminator wraps to UINT32_MAX, causing a heap out-of-bounds read that crashes the process. An unauthorized party who can supply crafted BSON input to an application using this API can cause a denial of service.2dCVE-2026-91103—21.3%
——6HP has identified and remediated multiple externally reported vulnerabilities within HPLIP. The findings affect several software components that could potentially enable remote code execution, privilege escalation, denial of service, information disclosure, or unauthorized file modification under certain conditions.4dCVE-2026-890287.5 HIG45.2%
——14MikroTik RouterOS before 7.24 contains a heap memory corruption vulnerability in the userspace SMB daemon that allows remote attackers to corrupt adjacent heap memory by supplying a crafted uniPwdLen value in the SMB1 SessionSetupAndX handler. An attacker can send a malformed SMB1 request with a uniPwdLen field that triggers an integer underflow, causing the resulting value to be used as the copy length in a memory copy operation into a smaller heap buffer, corrupting adjacent heap memory.3d