Malicious PDF — malware analysis report

Static analysis result for SHA-256 33b8d6211fb507e8…

MALICIOUS

PDF

73.6 KB Created: 2021-09-03 12:56:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 898e04a24fd3ea9bb395e3c9b10895b9 SHA-1: f2a04db4da707dbf2e241203202733449a510d10 SHA-256: 33b8d6211fb507e87625fc672fa4982a8e1e5f1452cc956a8815c749d9f8fae2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or redirection campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0bf3d766a0---pagumobevevov.pdf
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084bb1c0c788---79611126004.pdf
    • https://beautifullifeuk.com/wp-content/plugins/super-forms/uploads/php/files/313aea6a288c9e362c731d371f0f51ac/gixibibo.pdf
    • http://automsystem.com/UploadFile/file/20210514003431670.pdf
    • http://ubestsports.com/imager/files/20210609030352.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a563bcffc---pabufopasad.pdf
    • http://ktcyy.com/ckfinder/userfiles/files/ligolatato.pdf
    • http://hyundaihungthinh.com/uploads/images/files/kolapad.pdf
    • https://mosallaesf.ir/uploads/ck/files/wapelul.pdf
    • http://korean-school.hu/hangul/userfiles/file/kawusorapedu.pdf
    • https://jakspravnenapsa.cz/userfiles/file/79427419843.pdf
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160861a8e09e55---lusafogawubej.pdf
    • http://anhuicrew.com/upload_fck/file/2021-5-2/20210502090323258208.pdf
    • http://dh-life.com/ckfinder/userfiles/files/72674128483.pdf
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160949431a20b1---fitizumenukitodixub.pdf
    • http://amako-ra.com/wp-content/plugins/super-forms/uploads/php/files/ca4c70159bac9a4ecd5a0413b7aecaaa/wakirubonunaliv.pdf
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/bnbp60pmnambuv6t3565v4r6b7/fusaxideg.pdf
    • http://geoodwierty.pl/files/file/logerugarizajifo.pdf
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/8f1740473b1a10653516e607e0c17e9c/2737523761.pdf
    • http://vattucongtrinh.com/userfiles/file/zawutamede.pdf
    • http://belst.by/upload/file/54993078457.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=jurnal+annona+muricata+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://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bd2b.bin
94ccb52b99757b51ec02ca5c76447b80cec685d837472737e79e352bde3eca95
pdf-font-stream PDF embedded font (sfnt) at offset 0xBD2B 10572 bytes
font_01_sfnt_off0000d541.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD541 16792 bytes
font_02_sfnt_off0000ed53.bin
8a599e81681048e1ec6f7bf055e040c360cef079d61ca1198ba2e7e353c0c3f1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED53 16960 bytes