BaseCookie.js_output() does not neutralize embedded characters

http.cookies.Morsel.js_output() returns an inline <script> snippet and only escapes " for JavaScript string context. It does not neutralize the HTML parser-sensitive sequence </script> inside the generated script element. Mitigation base64-encodes the cookie value to disallow escaping using cookie value.

Expat Denial of Service via storeAtts() Quadratic Complexity

Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementType->defaultAtts to determine CDATA status. A remote unauthenticated attacker can supply a single well-formed XML document of a few megabytes to an application parsing untrusted XML to cause excessive CPU consumption, resulting in denial of service without requiring authentication, external entity resolution, or non-default parser options.

libssh2 Heap Out-of-Bounds Read via publickey subsystem

libssh2 through 1.11.1, fixed in commit a13bb6c, contains a missing bounds check vulnerability that allows a malicious SSH server to trigger an arbitrary-length heap out-of-bounds read and a free of an uninitialized pointer via the publickey subsystem. In libssh2_publickey_list_fetch(), the version 1 response parser reads a server-controlled comment_len value and advances the parse pointer without verifying sufficient bytes remain in the buffer, causing the out-of-bounds read to leak heap pointers from adjacent allocations defeating ASLR, followed by heap allocator state corruption when the error cleanup path frees an uninitialized pointer from a non-zeroed realloc() region.

libssh2 Double-Free Heap Corruption via sftp_open()

libssh2 through 1.11.1, fixed in commit 5e47761, contains a double-free vulnerability in the sftp_open() function in src/sftp.c that allows a malicious SSH server to corrupt the heap of any authenticated client opening an SFTP session. When a server responds to SSH_FXP_OPEN with SSH_FXP_STATUS containing FX_OK, the response data buffer is freed, and if a subsequent sftp_packet_require() call returns a specific error such as LIBSSH2_ERROR_CHANNEL_PACKET_EXCEEDED, the same pointer is freed a second time, enabling tcache dup conditions on glibc systems that allow overlapping allocations and function pointer overwrites.

libssh2 - Free of Uninitialized Pointer in publickey List Cleanup

libssh2 through 1.11.1 grows its publickey list with SSH2_REALLOC but does not zero-initialize new entries before parsing populates them, so a parse failure reaching the cleanup path leaves libssh2_publickey_list_free operating on an uninitialized entry. A malicious SSH server offering the publickey subsystem can use a malformed response to make cleanup free an uninitialized, attacker-influenceable attrs pointer in a connecting libssh2 client.

Storable versions before 3.41 for Perl have a signed integer overflow when deserializing a crafted SX_HOOK record

Storable versions before 3.41 for Perl have a signed integer overflow when deserializing a crafted SX_HOOK record. retrieve_hook_common reads a signed 32-bit item count from an SX_HOOK record and calls av_extend with that count plus one. A count of I32_MAX wraps the addition to a negative value. A crafted blob passed to thaw or retrieve triggers the overflow; av_extend receives the negative count and dies with a panic, terminating the deserialization.

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack

Perl versions before 5.40.5-RC1, from 5.41.0 before 5.42.3-RC1, from 5.43.0 before 5.43.11 have an integer overflow in S_measure_struct leading to an out-of-bounds heap read in pack and unpack. S_measure_struct adds each item's size times its repeat count to a running total with no overflow check, so a large repeat count in a pack or unpack template wraps the signed SSize_t total negative. The @, X, and x position codes then guard their moves with a signed length comparison that passes when the length is negative, advancing the buffer pointer out of bounds. A template derived from untrusted input can read heap memory past the buffer and return it to the caller.

libexpat: libexpat: Use-after-free vulnerability due to improper handling of XML CDATA sections

libexpat before 2.8.2 does not consider XML_TOK_DATA_CHARS in doCdataSection and thus lacks handler call depth tracking for various calls from within handlers in cases of a policy violation. Thus, a use-after-free can occur. NOTE: this issue exists because of an incomplete fix for CVE-2026-50219.

expat: libexpat: Integer Overflow Vulnerability Leading to Information Disclosure or Code Execution

xmlwf in libexpat before 2.8.2 has an integer overflow in endDoctypeDecl via NOTATION declarations.

libexpat: libexpat: Integer overflow in xmlwf can lead to information disclosure and arbitrary code execution.

xmlwf in libexpat before 2.8.2 has an integer overflow in resolveSystemId.

Integer Overflow in libexpat xmlwf Output File Handling

xmlwf in libexpat before 2.8.2 has an integer overflow for the output filename when -d outputDir is used.

Integer Overflow in libexpat copyString Function

libexpat before 2.8.2 has an integer overflow in copyString.

Integer Overflow in libexpat XML Parser

libexpat before 2.8.2 has an integer overflow in doProlog that is related to storeEntityValue and entity textLen.

libexpat: libexpat: Arbitrary code execution via integer overflow in XML_ParseBuffer

libexpat before 2.8.2 has an integer overflow in XML_ParseBuffer because it lacked a check that was present in XML_Parse.

libexpat: libexpat: Information disclosure and arbitrary code execution via integer overflow

libexpat before 2.8.2 has an integer overflow in getAttributeId.

libexpat before 2.8.2 has an integer overflow in addBinding.

libexpat: libexpat: Arbitrary code execution due to integer overflow in storeAtts

libexpat before 2.8.2 has an integer overflow in storeAtts.

expat: libexpat: Arbitrary Code Execution via Heap-based Buffer Overflow

In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.

Use-After-Free in libexpat's XML_ResumeParser Call Depth Tracking

libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).

Timing Side-Channel in Scalar Multiplication for Non-NIST EC Curves

Issue summary: The generic elliptic-curve scalar multiplication used for ECDSA and SM2 signature operations with curves that do not have a dedicated implementation leaks information about the secret nonce through timing. Impact summary: An attacker able to measure signing times may learn information about the per-signature secret nonce, which over many signatures can, via a lattice / Hidden Number Problem attack, lead to recovery of the private key. CWE: CWE-208: Observable Timing Discrepancy Description: The generic elliptic-curve scalar multiplication used for curves that do not have a dedicated constant-time implementation pads the secret scalar with non-constant-time BIGNUM operations, so the time taken depends on the value of the secret scalar derived from the ECDSA and SM2 nonce. The leak is very small; observing it requires a large number of measurements. The effect is largest for curves whose group order lies on a machine-word boundary, such as brainpoolP384r1. Applications using ECDSA signing over the Brainpool and other generic prime curves, and SM2 signing on platforms that use the generic implementation, are vulnerable to this issue. The NIST curves P-256, P-384 and P-521 use dedicated constant-time implementations and are not affected. FIPS Impact: no The FIPS modules are not affected: the approved NIST curves used in the FIPS provider have dedicated constant-time implementations and do not use the affected code path.