CVE-2020-36221
An integer underflow was discovered in OpenLDAP before 2.4.57 leading to slapd crashes in the Certificate Exact Assertion processing, result
CVSS
7.5
Alta
EPSS
85.0%
p100
KEV
—
Exploit Today
30
0-100
Publicado: 26 de jan. de 2021 · Última mod.: 14 de out. de 2026 · CWE-191
85.0%EPSS · 30 dias85.0%
2026-10-082026-11-05
An integer underflow was discovered in OpenLDAP before 2.4.57 leading to slapd crashes in the Certificate Exact Assertion processing, resulting in denial of service (schema_init.c serialNumberAndIssuerCheck).
- seclists.orghttp://seclists.org/fulldisclosure/2021/May/64
- seclists.orghttp://seclists.org/fulldisclosure/2021/May/65
- seclists.orghttp://seclists.org/fulldisclosure/2021/May/70
- bugs.openldap.orghttps://bugs.openldap.org/show_bug.cgi?id=9404
- bugs.openldap.orghttps://bugs.openldap.org/show_bug.cgi?id=9424
- git.openldap.orghttps://git.openldap.org/openldap/openldap/-/commit/38ac838e4150c626bbfa0082b7e2cf3a2bb4df31
- git.openldap.orghttps://git.openldap.org/openldap/openldap/-/commit/58c1748e81c843c5b6e61648d2a4d1d82b47e842
- git.openldap.orghttps://git.openldap.org/openldap/openldap/-/tags/OPENLDAP_REL_ENG_2_4_57
- lists.apache.orghttps://lists.apache.org/thread.html/r58af02e294bd07f487e2c64ffc0a29b837db5600e33b6e698b9d696b%40%3Cissues.bookkeeper.apache.org%3E
- lists.apache.orghttps://lists.apache.org/thread.html/rf4c02775860db415b4955778a131c2795223f61cb8c6a450893651e4%40%3Cissues.bookkeeper.apache.org%3E
- lists.debian.orghttps://lists.debian.org/debian-lts-announce/2021/02/msg00005.html
- security.netapp.comhttps://security.netapp.com/advisory/ntap-20210226-0002/
- support.apple.comhttps://support.apple.com/kb/HT212529
- support.apple.comhttps://support.apple.com/kb/HT212530
- support.apple.comhttps://support.apple.com/kb/HT212531
- www.debian.orghttps://www.debian.org/security/2021/dsa-4845
- seclists.orghttp://seclists.org/fulldisclosure/2021/May/64
- seclists.orghttp://seclists.org/fulldisclosure/2021/May/65
- seclists.orghttp://seclists.org/fulldisclosure/2021/May/70
- bugs.openldap.orghttps://bugs.openldap.org/show_bug.cgi?id=9404
CVECVSSEPSSKEVRExploitTítuloMod.
CVE-2026-1167888.2 ALT—
——0FreeSWITCH is an open-source software telecommunications platform. Before version 1.11.2, an integer underflow in switch_xml_decode() can cause an undersized heap allocation when an XML document declares an entity with an empty replacement value. Subsequent copying overruns the allocated buffer. An unauthenticated attacker who can reach a SIP profile with presence management enabled and DTD processing permitted can trigger the vulnerability through a crafted SIP PUBLISH request. Exploitation can corrupt heap memory and terminate the FreeSWITCH process, interrupting all active calls. This vulnerability is fixed in version 1.11.2.21hCVE-2026-1165697.5 ALT—
——0FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.2, msrp_parse_buffer() subtracted delimiter framing from a peer-controlled short segment whose MSRP byte range ended in * without first proving the segment was long enough. The unsigned result wrapped near SIZE_MAX and reached switch_msrp_msg_set_payload() as both an allocation size and memcpy length, while related pointer arithmetic could read before the receive buffer. The listener is disabled by default in msrp.conf.xml, but any deployment enabling an MSRP TCP or TLS port parses this framing before authentication. An unauthenticated network peer can corrupt memory and crash FreeSWITCH, dropping all active calls, although remote code execution has not been demonstrated. This issue is fixed in version 1.11.2.21hCVE-2026-1165687.5 ALT—
——0FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.2, rtmp_rtmp2rtpH264() trusted the length prefix of each inbound H.264 NAL unit without checking it against the bytes remaining in the RTMP message. An oversized declared unit underflowed the unsigned remaining-byte counter and advanced the parser beyond its receive buffer, where the next length-prefix read could crash the process. The flaw affects deployments that build and load mod_rtmp and accept video call sessions, commonly on TCP port 1935; placing the call requires a directory login where auth-calls is true, while no credentials are required where auth-calls is absent or false. A remote client can terminate FreeSWITCH and every active call, but the defect supplies no write primitive and memory disclosure has not been demonstrated. This issue is fixed in version 1.11.2.21hCVE-2026-1159287.5 ALT—
——0FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to 1.11.2, switch_core_media_add_crypto() passed the encoded key and salt length from an inbound SDP a=crypto attribute to switch_b64_decode() as the destination capacity. A zero-length key and salt made that capacity underflow, allowing the decoded attribute to overflow a fixed stack buffer with sender-chosen bytes before the call was answered. On the shipped external profile, an unauthenticated caller can reach the SDES-SRTP parser, while profiles that challenge inbound calls remain affected for senders who can authenticate; setting rtp_secure_media_inbound to false removes the path, and WebRTC DTLS-SRTP legs are unaffected. The overflow corrupts memory and can crash the FreeSWITCH process, dropping every active call, although remote code execution has not been demonstrated. This issue is fixed in version 1.11.2.21hCVE-2026-122992—24.9%
——7In G4KLX DStarGateway and F4FXL DStarGateway before 7b75de6, dstarCallsignToAPRS in APRSUtils.cpp has an integer underflow via an empty RS-MS1A sender field.2dCVE-2026-1217277.5 ALT33.2%
——10Kore before 4.3.0 contains an integer underflow vulnerability in HTTP request body handling that allows unauthenticated attackers to bypass http_body_max by sending more body bytes than declared. Attackers can send oversized first segments over many concurrent POST, PUT or DELETE connections, wrapping content_length to grow buffers unbounded and exhaust worker memory.3d