TLS ClientHello (JA4)

t13d301300_1d37bd780c83_5ae85263eb3b

first seen 2026-07-01 14:43 · last seen 2026-09-13 07:17 · 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

t13d301300_1d37bd780c83_5ae85263eb3b

Mozilla/5.0 (X11; Linux x86_64; rv:142.0) Gecko/…

User-Agent claims Firefox 142.0

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 (X11; Linux x86_64; rv:142.0) Gecko/20100101 Firefox/142.0
Claimed version	142.0
Measured versions	146.0.1, 152.0.1, 154.0, 140.0.2, 151.0.4, 151.0.2, 139.0, 153.0.1, 155.0, 152.0.5, 153.0.3, 142.0.1, 153.0.4, 152.0.6, 150.0.2, 135.0, 132.0, 152.0.3, 148.0.2, 137.0, 141.0, 155.0.1, 153.0, 151.0.3, 144.0.2, 154.0.1, 134.0, 152.0.4, 151.0
Layer	cipher suites differ
JA4 label	unlabeled

medium

2026-07-22

2026-09-13

t13d301300_1d37bd780c83_5ae85263eb3b

Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv…

User-Agent claims Firefox 139.0

TLS cipher list matches no measured Firefox capture

Full User-Agent	Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:139.0) Gecko/20100101 Firefox/139.0
Claimed version	139.0
Measured versions	146.0.1, 152.0.1, 154.0, 140.0.2, 151.0.4, 151.0.2, 139.0, 153.0.1, 155.0, 152.0.5, 153.0.3, 142.0.1, 153.0.4, 152.0.6, 150.0.2, 135.0, 132.0, 152.0.3, 148.0.2, 137.0, 141.0, 155.0.1, 153.0, 151.0.3, 144.0.2, 154.0.1, 134.0, 152.0.4, 151.0
Layer	cipher suites differ
JA4 label	unlabeled

medium

2026-07-02

Last 7 days (4 observations)

Distinct clients per day (last 30 days, peak 2/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	`30`
Extension count	`13`
ALPN	`00`
Ciphers	`002f, 0033, 0035, 0039, 003c, 003d, 0067, 006b, 009c, 009d, 009e, 009f, 1301, 1302, 1303, c009, c00a, c013, c014, c023, c024, c027, c028, c02b, c02c, c02f, c030, cca8, cca9, ccaa`
Extensions	`000a, 000b, 000d, 0016, 0017, 001b, 0023, 002b, 002d, 0031, 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	`t13d301300_002f,0033,0035,0039,003c,003d,0067,006b,009c,009d,009e,009f,1301,1302,1303,c009,c00a,c013,c014,c023,c024,c027,c028,c02b,c02c,c02f,c030,cca8,cca9,ccaa_000a,000b,000d,0016,0017,001b,0023,002b,002d,0031,0033,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)	`t13d301300_8d44cdc55eec_02fb374a4035`
JA4_ro (sample)	`t13d301300_1302,1303,1301,c02c,c030,009f,cca9,cca8,ccaa,c02b,c02f,009e,c024,c028,006b,c023,c027,0067,c00a,c014,0039,c009,c013,0033,009d,009c,003d,003c,0035,002f_ff01,0000,000b,000a,0023,0016,0017,0031,000d,002b,002d,0033,001b_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
`ge11nn15enus_42d7418375b7_000000000000_000000000000`	13
`ge11nn12enus_9a9494a1019e_000000000000_000000000000`	7
`ge11nn040000_80c20a6e2957_000000000000_000000000000`	1
`he11nn120000_08e84d149b43_000000000000_000000000000`	1
`ge11nn120000_08e84d149b43_000000000000_000000000000`	1
`ge11nn040000_11cd5a654206_000000000000_000000000000`	1
`ge11nn07en00_94ab2ecd7761_000000000000_000000000000`	1
`ge11nn08en00_21593d68c304_000000000000_000000000000`	1
`ge11nn06enus_f03ddaa65e26_000000000000_000000000000`	1
`ge11nn06enus_f73f0198971e_000000000000_000000000000`	1

TCP SYN (p0f)

fingerprint	co-occurrences
`4:56+8:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	9
`4:52+12:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	4
`4:51+13:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	3
`4:47+17:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	2
`4:118+10:0:1460:62727,7:mss,sok,ts,nop,ws:df,id+:0`	2
`4:51+13:0:1452:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	2
`4:48+16:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	1
`4:50+14:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	1
`4:49+15:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	1
`4:41+23:0:1460:mss*44,7:mss,sok,ts,nop,ws:df,id+:0`	1

TCP SYN (JA4T)

fingerprint	co-occurrences
`64240_2-4-8-1-3_1460_7`	23
`62727_2-4-8-1-3_1460_7`	2
`64240_2-4-8-1-3_1452_7`	2
`64860_2-4-8-1-3_1410_7`	1

User-Agent

fingerprint	co-occurrences
`Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/142.0.0.0 Safari/537.36`	13
`Mozilla/5.0 (X11; Linux x86_64; rv:142.0) Gecko/20100101 Firefox/142.0`	7
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36`	2
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36`	1
`Ruby`	1
`Mastodon/4.5.9 (http.rb/5.3.1; +https://mastodon.cloud/) Bot`	1
`Mastodon/4.6.2 (http.rb/5.3.1; +https://mastodon.social/) Bot`	1
`Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:139.0) Gecko/20100101 Firefox/139.0`	1
`SoonBot/1.0 (+https://soon.ciaransplayground.com)`	1

Country

fingerprint	co-occurrences
`US` · United States	18
`DE` · Germany	3
`IN` · India	2
`IE` · Ireland	2
`NL` · Netherlands	1
`GB` · United Kingdom	1
`FI` · Finland	1

Network (ASN)

fingerprint	co-occurrences
`AS14061` · DigitalOcean, LLC	21
`AS24940` · Hetzner Online GmbH	3
`AS14618` · Amazon.com, Inc.	2
`AS215733` · Blacknight Internet Solutions Limited	2