csirt@kutim:~/threat-intel/cve/CVE-2023-48230

Katalog CVE

CVSS 9.8 · Critical EPSS 1,9%

Kerentanan Buffer Underwrite ('Buffer Underflow') pada capnproto. Skor CVSS 3.1 9.8 (Critical) menurut NVD.

Deskripsi (NVD)

Cap'n Proto is a data interchange format and capability-based RPC system. In versions 1.0 and 1.0.1, when using the KJ HTTP library with WebSocket compression enabled, a buffer underrun can be caused by a remote peer. The underrun always writes a constant value that is not attacker-controlled, likely resulting in a crash, enabling a remote denial-of-service attack. Most Cap'n Proto and KJ users are unlikely to have this functionality enabled and so unlikely to be affected. Maintainers suspect only the Cloudflare Workers Runtime is affected. If KJ HTTP is used with WebSocket compression enabled, a malicious peer may be able to cause a buffer underrun on a heap-allocated buffer. KJ HTTP is an optional library bundled with Cap'n Proto, but is not directly used by Cap'n Proto. WebSocket compression is disabled by default. It must be enabled via a setting passed to the KJ HTTP library via `HttpClientSettings` or `HttpServerSettings`. The bytes written out-of-bounds are always a specific constant 4-byte string `{ 0x00, 0x00, 0xFF, 0xFF }`. Because this string is not controlled by the attacker, maintainers believe it is unlikely that remote code execution is possible. However, it cannot be ruled out. This functionality first appeared in Cap'n Proto 1.0. Previous versions are not affected. This issue is fixed in Cap'n Proto 1.0.1.1.

Rincian

Terbit di NVD
21 November 2023
Terakhir diubah
17 Juni 2026
Status NVD
Modified
CVSS 3.1
9.8 (Critical), sumber NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-124: Buffer Underwrite ('Buffer Underflow')
CWE-787: Out-of-bounds Write
EPSS (30 hari)
1,9% peluang dieksploitasi; lebih tinggi dari 79,0% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
capnproto capnproto Versi 1.0.0
capnproto capnproto Versi 1.0.1

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:10 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.