curl: TLS verifyhost bypass in rustls, mbedTLS, and wolfSSL when verifypeer=0

The now-well-known CURLOPTSSLVERIFYHOST-bypass-when-CURLOPTSSLVERIFYPEER=0 defect exists in three of curl's TLS backends: rustls EXPERIMENTAL, mbedTLS, and wolfSSL DNS hostnames only. The documented contract at docs/libcurl/opts/CURLOPTSSLVERIFYPEER.md:57-59: The check that the host name in the...

curl: HTTP/2 proxy CONNECT tunnel unbounded 1xx chain (missing Curl_bump_headersize cap in cf-h2-proxy.c)

A malicious HTTPS-on-HTTP/2 proxy can grow a libcurl client's resident set without bound during the CONNECT phase by streaming 1xx informational responses. The CVE-2023-38039 cap MAXHTTPRESPHEADERSIZE, 300 KiB, enforced through Curlbumpheadersize is not applied on the HTTP/2 proxy path. The HTTP/...

curl: HSTS multi-trailing-dot bypass-ish: possible incomplete fix for CVE-2022-30115

Hi all, Honestly, I'm not completely certain about this issue, but I think the CVE-2022-30115 fix "HSTS bypass via trailing dot" is incomplete: the same asymmetry exists for hostnames with two or more trailing dots, so http://example.com../ still gets sent in plaintext when there's a valid HSTS...

curl: Credentials forwarded to HTTP after HTTPS→HTTP same-port redirect — url_set_data_creds uses scheme-blind comparator

Hi all, The recent creds: hold credentials refactor — commit 8f71d0fde5 2026-05-11 https://github.com/curl/curl/commit/8f71d0fde5 — introduced a credential-leak regression on HTTPS→HTTP same-port redirects. -u user:pass and --oauth2-bearer both end up in cleartext after a 302 from https://h:N/ to...

curl: CURLOPT_HSTS_CTRL disables shared HSTS without share guard — use-after-free and double-free

Hi all, CURLOPTHSTSCTRL set to a value without CURLHSTSENABLE unconditionally frees the easy's HSTS object — even when that object is shared via a CURLSH. The result is a use-after-free and a double-free on the shared 48-byte struct hsts block when the share or any other linked easy is later torn...

curl: CVE-2026-8932: incomplete mTLS config matching in conn reuse

Hi all, This report and my multiple subsequent ones may come as a surprise, as I was assured that curl now had zero vulnerabilities in it. Nonetheless, I think the CVE-2022-27782 fix "TLS and SSH connection too eager reuse", commit f18af4f874 2022-05-09, "tls: check more TLS details for connectio...

curl: CVE-2026-8924: trailing dot domain super cookie

Summary: A PSL-enabled curl build rejects a canonical public suffix cookie such as Domain=co.uk, but accepts the trailing-dot variant Domain=co.uk. when the request host also uses a trailing dot. In the reproduced case, a response from foo.co.uk. sets Set-Cookie: trail=1; Domain=co.uk.; Path=/, a...

curl: Kerberos/SPNEGO Connection Reuse Vulnerability

Kerberos/SPNEGO Connection Reuse Vulnerability in curl Summary curl reuses HTTP connections across different users without checking Kerberos state. User B's request can inherit User A's GSS security context, allowing authentication bypass. Affected Versions All curl versions with Kerberos support...

Khan Academy: 1-Click Account Takeover via Open Redirect through Regex Bypass in Domain Validation

A vulnerability was discovered in the Khan Academy platform that allowed an attacker to achieve full account takeover of any user. The vulnerability was caused by an unescaped dot flaw in the regular expression used to validate redirect URLs. This allowed the attacker to register a malicious doma...

Monero: wallet-rpc describe_transfer uses real_output_in_tx_index instead of real_output: cold-wallet pre-sign review shows wrong ring member

The wallet-rpc method "describetransfer" was found to use the wrong index when retrieving information about the ring members for each input. Instead of using the "realoutput" index, which represents the position of the real entry in the ring, it used the "realoutputintxindex", which represents th...

Node.js: HTTP Request Smuggling via Connection: close<TAB> in Node.js llhttp parser

A vulnerability was discovered in the Node.js HTTP server where it ignores the "Connection: close" header when the token is followed by a tab character. This allows an attacker to send a second request on the same connection, even after the first request should have closed the connection...

Liberapay: another liberapay member team twitter account broken Link Hijacking via Expired Twitter Account Link

Hello again i discovered that there is another Liberapay profile of Liberapay team member at liberapay.com/mdvhimself contains a link to an expired Twitter account, creating a Broken Link Hijacking BLH vulnerability. An attacker could register the expired handle and control what appears to be an...

Liberapay: Liberapay member team twitter account broken Link Hijacking via Expired Twitter Account Link

The profile of a Liberapay team member contained a link to an expired Twitter account, creating a broken link hijacking vulnerability. The expired Twitter account link was displayed on the member's Liberapay profile and donation page, falsely confirming to donors that the account was legitimate a...

curl: CVE-2026-8458: wrong reuse for different services

Summary: I found an incomplete-fix variant of CVE-2026-5545 in curl/libcurl 8.20.0. libcurl 8.20.0 still wrongly reuses an HTTP Negotiate-authenticated connection for a later request to the same host even when the requested service principal changes via CURLOPTSERVICENAME / --service-name. In my...

Node.js: Proxy credentials leaked in ERR_PROXY_TUNNEL error message

Vulnerability description not provided...

curl: Shared HSTS cache accessed without lock

This is finding F5 in Andrew's report https://github.com/curl/curl/blob/455bebc2c7/lib/hsts.cL160-L168 https://github.com/curl/curl/blob/455bebc2c7/lib/http.cL3571 https://github.com/curl/curl/blob/455bebc2c7/lib/url.cL1441 https://github.com/curl/curl/blob/455bebc2c7/lib/url.cL265...

curl: CVE-2026-8286: wrong STARTTLS connection reuse

A vulnerability was found in the Curl library that allowed a plain-text connection to reuse an existing SSL-upgraded connection without verifying the SSL configuration. This could lead to a man-in-the-middle attack if an attacker was able to intercept the initial STARTTLS upgrade. The issue was...

curl: CURLOPT_PROXY_CRLFILE / CURLOPT_PROXY_ISSUERCERT / CURLOPT_PROXY_ISSUERCERT_BLOB silently ignored on backends that don't support them

From the Mythos report 2026-05-06 F1. CURLOPTPROXYCRLFILE / CURLOPTPROXYISSUERCERT / CURLOPTPROXYISSUERCERTBLOB silently ignored on backends that don't support them — severity Low https://github.com/curl/curl/blob/455bebc2c7/lib/setopt.cL1786-L1797...

curl: mbedTLS private-key blob null-termination asymmetry in lib/vtls/mbedtls.c (mbed_load_privkey)

Summary: In lib/vtls/mbedtls.c, function mbedloadprivkey lines 653-738 passes raw sslkeyblob-data and sslkeyblob-len directly to mbedtlspkparsekey at lines 706-708 mbedTLS 4.x branch and 718-722 mbedTLS 3.x branch, without ensuring null-termination. The mbedTLS API contract for mbedtlspkparsekey...

PortSwigger Web Security: UI Consent Bypass via Comma Injection in `addAutoApproveTarget` — User-Approval Dialog and Persistence Layer Disagree on Target Scope, Yielding Authen

A vulnerability was discovered in Burp Suite MCP Server BApp v1.2.1 where the addAutoApproveTarget function failed to validate the hostnames passed to it. This allowed a malicious MCP client to inject a comma-separated hostname, which was then persisted as multiple independent allow-list entries...