TLS ClientHello (JA4)

t13d1712h1_ab0a1bf427ad_8e6e362c5eac

first seen 2026-06-19 16:21 · last seen 2026-10-31 14:18 · JSON

Inconsistencies

User-Agents observed with this fingerprint that contradict what it proves at the wire. all inconsistencies →

fingerprint User-Agent claims wire shows confidence seen first seen last seen

t13d1712h1_ab0a1bf427ad_8e6e362c5eac

Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:133…

User-Agent claims Firefox 133.0

TLS cipher list matches no measured Firefox capture

The offered TLS cipher suites match no controlled capture of Firefox. Cipher lists are very stable per browser, so a different one is a real inconsistency — though a TLS-inspecting proxy re-originating the handshake is an honest cause, which holds this at medium.

Full User-Agent	Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:133.0) Gecko/20100101 Firefox/133.0
Claimed version	133.0
Measured versions	146.0.1, 154.0, 140.0.2, 157.0.1, 151.0.2, 155.0, 153.0.3, 142.0.1, 153.0.4, 152.0.6, 150.0.2, 135.0, 156.0.1, 132.0, 152.0.3, 141.0, 153.0, 151.0.3, 156.0, 152.0.4, 151.0, 152.0.1, 151.0.4, 139.0, 153.0.1, 158.0.1, 152.0.5, 157.0, 158.0, 148.0.2, 137.0, 155.0.1, 159.0, 144.0.2, 154.0.1, 134.0
Layer	cipher suites differ
JA4 label	unlabeled

medium

2026-10-27

Last 7 days (6 observations)

Distinct clients per day (last 30 days, peak 3/day)

Distinct clients are counted by IP-hash per complete UTC day — unlike observation counts this is insensitive to one chatty client, but NAT merges clients and address rotation splits them.

Decomposed attributes

Protocol	`t (TLS over TCP)`
TLS version	`13`
SNI	`d (domain)`
Cipher count	`17`
Extension count	`12`
ALPN	`h1`
Ciphers	`0067, 006b, 009e, 009f, 1301, 1302, 1303, c023, c024, c027, c028, c02b, c02c, c02f, c030, cca8, cca9`
Extensions	`000a, 000b, 000d, 0016, 0017, 0023, 002b, 002d, 0033, ff01`
Signature algorithms	`0905, 0906, 0904, 0403, 0503, 0603, 0807, 0808, 081a, 081b, 081c, 0809, 080a, 080b, 0804, 0805, 0806, 0401, 0501, 0601, 0303, 0301, 0302, 0402, 0502, 0602`
JA4_r	`t13d1712h1_0067,006b,009e,009f,1301,1302,1303,c023,c024,c027,c028,c02b,c02c,c02f,c030,cca8,cca9_000a,000b,000d,0016,0017,0023,002b,002d,0033,ff01_0905,0906,0904,0403,0503,0603,0807,0808,081a,081b,081c,0809,080a,080b,0804,0805,0806,0401,0501,0601,0303,0301,0302,0402,0502,0602`
JA4_o (sample)	`t13d1712h1_fd0eb050439a_ec3b10441c8f`
JA4_ro (sample)	`t13d1712h1_1302,1303,1301,c02c,c030,c02b,c02f,cca9,cca8,c024,c028,c023,c027,009f,009e,006b,0067_ff01,0000,000b,000a,0023,0010,0016,0017,000d,002b,002d,0033_0905,0906,0904,0403,0503,0603,0807,0808,081a,081b,081c,0809,080a,080b,0804,0805,0806,0401,0501,0601,0303,0301,0302,0402,0502,0602`

Co-observed signals

Signals from other families seen in the same observation. A fingerprint spread thinly across many lower-layer signatures is a classic inconsistency signal.

HTTP request (JA4H)

fingerprint	co-occurrences
`ge11nn10engb_ec5486a7d5a7_000000000000_000000000000`	185
`ge11nn050000_be0d0b335e46_000000000000_000000000000`	22
`ge11nn06en00_7eb5f6c8ec48_000000000000_000000000000`	16
`ge11nn040000_e1d2031bdfea_000000000000_000000000000`	7
`ge11nn050000_dac78f95d824_000000000000_000000000000`	3
`ge20nn08engb_c4bf040e0aa1_000000000000_000000000000`	3
`ge11nn050000_7054e5f9be97_000000000000_000000000000`	3
`ge11nn05enus_91bf09848158_000000000000_000000000000`	2
`ge11nn050000_444220f7ef68_000000000000_000000000000`	2
`ge11nn07enus_632e5de0fb19_000000000000_000000000000`	2

HTTP/2 frames (Akamai)

fingerprint	co-occurrences
`1:4096;2:0;4:65535;5:16384;3:100;6:65536\|16777216\|0\|m,a,s,p` Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1.The fingerprint page shows the full measured match list. More on the catalog.	3

TCP SYN (p0f)

fingerprint	co-occurrences
`4:43+21:0:1460:mss*44,10:mss,sok,ts,nop,ws::0`	190
`4:53+11:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	6
`4:53+11:0:1460:mss*44,10:mss,sok,ts,nop,ws:df,id+:0`	4
`4:41+23:0:1460:mss*44,10:mss,sok,ts,nop,ws::0`	4
`4:48+16:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	3
`4:52+12:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	3
`4:53+11:0:1460:65535,9:mss,sok,ts,nop,ws:df,id+:0`	3
`4:117+11:0:1460:mss*44,8:mss,nop,ws,nop,nop,sok:df,id+,ecn:0`	3
`4:49+15:0:1460:65535,6:mss,nop,ws,nop,nop,ts,sok,eol+1:df,ecn:0`	3
`4:110+18:0:1460:62727,7:mss,sok,ts,nop,ws:df,id+:0`	3

TCP SYN (JA4T)

fingerprint	co-occurrences
`64240_2-4-8-1-3_1460_10`	205
`64240_2-4-8-1-3_1460_7`	14
`62727_2-4-8-1-3_1460_7`	4
`64240_2-1-3-1-1-4_1460_8`	4
`65535_2-1-3-1-1-8-4-0-0_1460_6`	4
`65535_2-1-3-1-1-8-4-0-0_1440_6`	4
`65535_2-1-3-1-1-8-4-0-0_1452_6`	4
`65535_2-4-8-1-3_1460_9`	3
`64240_2-4-8-1-3_1460_8`	3
`64800_2-4-8-1-3_1440_9`	3

User-Agent

fingerprint	co-occurrences
`uk-nhs-data/0.0 (internal fraud-research)`	194
`startup-radar/0.1 (+research; contact: you@example.com)`	13
`Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36`	5
`Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 Chrome/116.0.0.0 Safari/537.36`	4
`Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/44.0.2403.157 Safari/537.36`	4
`python-httpx/0.28.1`	3
`Mozilla/5.0 (Macintosh; Intel Mac OS X 14_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126 Safari/537.36 lightdrift-research`	3
`Mozilla/5.0`	2
`Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:133.0) Gecko/20100101 Firefox/133.0`	2
`Mozilla/5.0 (Windows NT 10.0; Win64; x64)`	2

Country

fingerprint	co-occurrences
`GB` · United Kingdom	196
`US` · United States	21
`NL` · Netherlands	16
`DE` · Germany	3
`SG` · Singapore	2
`FR` · France	2
`CN` · China	2
`ES` · Spain	2
`AT` · Austria	2
`JP` · Japan	1

Network (ASN)

fingerprint	co-occurrences
`AS8468` · ENTANET International Limited	194
`AS210976` · Timeweb, LLP	12
`AS16509` · Amazon.com, Inc.	5
`AS7018` · AT&T Enterprises, LLC	5
`AS22773` · Cox Communications Inc.	4
`AS9009` · M247 Europe SRL	3
`AS212238` · Datacamp Limited	3
`AS29802` · HIVELOCITY, Inc.	3
`AS211507` · Julian Achter	3
`AS6079` · RCN	3

TLS supported groups

fingerprint	co-occurrences
`11ec,001d,0017,001e,0018,0019,0100,0101` Match?Exact match in Thumbprint's published controlled catalog captures: python-httpx 0.28.1, python-requests 2.34.2, curl 8.23.0, +4 more.The fingerprint page shows the full measured match list. More on the catalog.	23