Impact Cloudflare quiche was discovered to be vulnerable to incorrect congestion window growth, which could cause it to send data at a rate faster than the path might actually support. An unauthenticated remote attacker can exploit the vulnerability by first completing a handshake and initiating a congestion-controlled data transfer towards itself. Then, it could manipulate the victim's congestion control state by sending ACK frames exercising an opportunistic ACK attack; see RFC 9000 Section 21.4. The victim could grow the congestion window beyond typical expectations and allow more bytes in flight than the path might really support. Patches quiche 0.24.4 is the earliest version containing the fix for this issue.

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - Impact Cloudflare quiche was discovered to be vulnerable to incorrect congestion window growth, which
    could cause it to send data at a rate faster than the path might actually support. An unauthenticated
    remote attacker can exploit the vulnerability by first completing a handshake and initiating a congestion-
    controlled data transfer towards itself. Then, it could manipulate the victim's congestion control state
    by sending ACK frames exercising an opportunistic ACK attack; see RFC 9000 Section 21.4. The victim could
    grow the congestion window beyond typical expectations and allow more bytes in flight than the path might
    really support. Patches quiche 0.24.4 is the earliest version containing the fix for this issue.
    (CVE-2025-4820)

  - Impact Cloudflare quiche was discovered to be vulnerable to incorrect congestion window growth, which
    could cause it to send data at a rate faster than the path might actually support. An unauthenticated
    remote attacker can exploit the vulnerability by first completing a handshake and initiating a congestion-
    controlled data transfer towards itself. Then, it could manipulate the victim's congestion control state
    by sending ACK frames covering a large range of packet numbers (including packet numbers that had never
    been sent); see RFC 9000 Section 19.3. The victim could grow the congestion window beyond typical
    expectations and allow more bytes in flight than the path might really support. In extreme cases, the
    window might grow beyond the limit of the internal variable's type, leading to an overflow panic. Patches
    quiche 0.24.4 is the earliest version containing the fix for this issue. (CVE-2025-4821)

  - Cloudflare quiche was discovered to be vulnerable to an infinite loop when sending packets containing
    RETIRE_CONNECTION_ID frames. QUIC connections possess a set of connection identifiers (IDs); see Section
    5.1 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-5.1 . Once the QUIC handshake
    completes, a local endpoint is responsible for issuing and retiring Connection IDs that are used by the
    remote peer to populate the Destination Connection ID field in packets sent from remote to local. Each
    Connection ID has a sequence number to ensure synchronization between peers. An unauthenticated remote
    attacker can exploit this vulnerability by first completing a handshake and then sending a specially-
    crafted set of frames that trigger a connection ID retirement in the victim. When the victim attempts to
    send a packet containing RETIRE_CONNECTION_ID frames, Section 19.16 of RFC 9000
    https://datatracker.ietf.org/doc/html/rfc9000#section-19.6 requires that the sequence number of the
    retired connection ID must not be the same as the sequence number of the connection ID used by the packet.
    In other words, a packet cannot contain a frame that retires itself. In scenarios such as path migration,
    it is possible for there to be multiple active paths with different active connection IDs that could be
    used to retire each other. The exploit triggered an unintentional behaviour of a quiche design feature
    that supports retirement across paths while maintaining full connection ID synchronization, leading to an
    infinite loop.This issue affects quiche: from 0.15.0 before 0.24.5. (CVE-2025-7054)

  - A mismatch caused by client-triggered server-sent stream resets between HTTP/2 specifications and the
    internal architectures of some HTTP/2 implementations may result in excessive server resource consumption
    leading to denial-of-service (DoS). By opening streams and then rapidly triggering the server to reset
    them—using malformed frames or flow control errors—an attacker can exploit incorrect stream accounting.
    Streams reset by the server are considered closed at the protocol level, even though backend processing
    continues. This allows a client to cause the server to handle an unbounded number of concurrent streams on
    a single connection. This CVE will be updated as affected product details are released. (CVE-2025-8671)

  - In some circumstances, when DNSdist is configured to use the nghttp2 library to process incoming DNS over
    HTTPS queries, an attacker might be able to cause a denial of service by crafting a DoH exchange that
    triggers an unbounded I/O read loop, causing an unexpected consumption of CPU resources. (CVE-2025-30187)

There are packages installed that are affected by multiple vulnerabilities referenced in the following CVEs:

  - Impact Cloudflare quiche was discovered to be vulnerable to incorrect congestion window growth, which
    could cause it to send data at a rate faster than the path might actually support. An unauthenticated
    remote attacker can exploit the vulnerability by first completing a handshake and initiating a congestion-
    controlled data transfer towards itself. Then, it could manipulate the victim's congestion control state
    by sending ACK frames exercising an opportunistic ACK attack; see RFC 9000 Section 21.4. The victim could
    grow the congestion window beyond typical expectations and allow more bytes in flight than the path might
    really support. Patches quiche 0.24.4 is the earliest version containing the fix for this issue.
    (CVE-2025-4820)

  - Impact Cloudflare quiche was discovered to be vulnerable to incorrect congestion window growth, which
    could cause it to send data at a rate faster than the path might actually support. An unauthenticated
    remote attacker can exploit the vulnerability by first completing a handshake and initiating a congestion-
    controlled data transfer towards itself. Then, it could manipulate the victim's congestion control state
    by sending ACK frames covering a large range of packet numbers (including packet numbers that had never
    been sent); see RFC 9000 Section 19.3. The victim could grow the congestion window beyond typical
    expectations and allow more bytes in flight than the path might really support. In extreme cases, the
    window might grow beyond the limit of the internal variable's type, leading to an overflow panic. Patches
    quiche 0.24.4 is the earliest version containing the fix for this issue. (CVE-2025-4821)

  - Cloudflare quiche was discovered to be vulnerable to an infinite loop when sending packets containing
    RETIRE_CONNECTION_ID frames. QUIC connections possess a set of connection identifiers (IDs); see Section
    5.1 of RFC 9000 https://datatracker.ietf.org/doc/html/rfc9000#section-5.1 . Once the QUIC handshake
    completes, a local endpoint is responsible for issuing and retiring Connection IDs that are used by the
    remote peer to populate the Destination Connection ID field in packets sent from remote to local. Each
    Connection ID has a sequence number to ensure synchronization between peers. An unauthenticated remote
    attacker can exploit this vulnerability by first completing a handshake and then sending a specially-
    crafted set of frames that trigger a connection ID retirement in the victim. When the victim attempts to
    send a packet containing RETIRE_CONNECTION_ID frames, Section 19.16 of RFC 9000
    https://datatracker.ietf.org/doc/html/rfc9000#section-19.6 requires that the sequence number of the
    retired connection ID must not be the same as the sequence number of the connection ID used by the packet.
    In other words, a packet cannot contain a frame that retires itself. In scenarios such as path migration,
    it is possible for there to be multiple active paths with different active connection IDs that could be
    used to retire each other. The exploit triggered an unintentional behaviour of a quiche design feature
    that supports retirement across paths while maintaining full connection ID synchronization, leading to an
    infinite loop.This issue affects quiche: from 0.15.0 before 0.24.5. (CVE-2025-7054)

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the 7b0cbc73-9955-11f0-b6e2-6805ca2fa271 advisory.

    Quiche Releases reports:
    This update includes 2 security fixes:

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
436214	Alpine: multiple dnsdist packages: security update to 2.0.1-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	high
436214	Alpine: multiple dnsdist packages: security update to 2.0.1-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	high
435449	Alpine: multiple dnsdist packages: security update to 1.9.11-r0	Tenable Cloud Security	Alpine Linux Local Security Checks	high
435449	Alpine: multiple dnsdist packages: security update to 1.9.11-r0	Tenable Self-Hosted Container Security	Alpine Linux Local Security Checks	high
265997	FreeBSD : quiche -- Multiple vulnerabilities (7b0cbc73-9955-11f0-b6e2-6805ca2fa271)	Nessus	FreeBSD Local Security Checks	high

Detections

Analytics

CVE-2025-4820

medium

Tenable Plugins

high

high

high

high

high