Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c55c942dde92ab6…

MALICIOUS

PDF

72.7 KB Created: 2021-05-12 15:33:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a901bf6ad10a619fdff74a0445ee2b6 SHA-1: c6e4c0b130d60565ba7fd6fd36a4b94ade26ac76 SHA-256: 1c55c942dde92ab6a2313149fc8c8565a8d9afb68627ed626901b9011d6d4069
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains numerous links to external websites, many of which are hosted on compromised WordPress sites using form-building plugins. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as a phishing trojan. The presence of embedded URLs and the 'link farm' heuristic suggest the document's primary purpose is to redirect users to potentially malicious content or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160932e272d092---fizanubibemisu.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e461353dd2---19373725070.pdf
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/k1k9ahjdnpe0hegpqkp32e4d9f/xujadoxikodanurerivu.pdf
    • http://berbun.com/user_img/file/motukefuwojomomowosi.pdf
    • https://londonvipchauffeur.co.uk/wp-content/plugins/super-forms/uploads/php/files/b2cc828c14b368967e275597fec37adb/dowezasaranejut.pdf
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085af8f08a2f---25456257397.pdf
    • http://miamiwars.pl/wp-content/plugins/super-forms/uploads/php/files/1cfd6faf6d5a979d9f530eb3dbca656c/wifurimoxegevosepeliroriv.pdf
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16098e67238902---64629656697.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/16082eef23b214---14797332658.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16087789356b4c---tadijogawodewumab.pdf
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/743f5d2c94ead95d4dbcf65d7dd2cb01/kofapamagologu.pdf
    • http://pcmcpropertyblog.com/wp-content/plugins/super-forms/uploads/php/files/10d84b8f6a613f3b9491e33c84aa1787/kibutoporuborexegi.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c05de30f9---91868327826.pdf
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/68e3aa7fa8e92f3cf9aad0d0f68c14c4/21532065669.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/ijkienmkmpf4jp61ckgr5jfq3m/31734919020.pdf
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/73929148da03098abca53ade5d256ca8/xarutugedu.pdf
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608ab55f2ba8c---rimademuvowufikofaz.pdf
    • https://beaufortbond.com/wp-content/plugins/super-forms/uploads/php/files/3dc1fe01f938372b23b4121d44d39e52/koredatujematulizafuzivo.pdf
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16078afc56a1e5---4592609082.pdf
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1607155944e322---51057995824.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=gentoo+install+guide+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e044.bin
2047daf77b6f13476658983b0381d9998b4520432197c9fc3ff2766f1dab9214
pdf-font-stream PDF embedded font (sfnt) at offset 0xE044 5144 bytes
font_01_sfnt_off0000f1e0.bin
03c4d6d5d7dc0b0fb3ee8c3a3292a3cc8e9eb88062613c63d7e47a10416ac364
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E0 10496 bytes