Malicious PDF — malware analysis report

Static analysis result for SHA-256 837db173910f0976…

MALICIOUS

PDF

76.7 KB Created: 2021-06-26 00:19:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d7f027091f9b7fba3ee74154d1aa1918 SHA-1: bddab517b5970ec65ebb9e4c8f066ac492d89357 SHA-256: 837db173910f0976517de87ff401f886352c72df124bd10bf840f11e15893fca
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 https://drafthe.ru/uplcv?utm_term=grant+gustin+annie+are+you+okay
    • http://komputerzagrosze.pl/userfiles/file/povujolup.pdf
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/3070dc7207366287df2c0e2fd0d5d560/63698491744.pdf
    • https://go2germany.ru/files/file/94892607781.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbc1b7851bc---zupuxedeperazubebo.pdf
    • http://princeworldwide.com/multimedia/userfiles/file/bevifebepinusidaputiget.pdf
    • http://belgium-ex.com/images/blog//file/28589359956.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160817ffe3b498---pobusezusugosejuxab.pdf
    • https://rclurie.com/wp-content/plugins/super-forms/uploads/php/files/b8e44f49c1029332365967afce0764b8/ximofurevuramut.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16076a96e0b04c---wofokudofazij.pdf
    • http://aunay-sous-auneau.fr/ckfinder/userfiles/files/85605449622.pdf
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609e62527451d---60247530921.pdf
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606d174d8e21c---vutudewujojuvowik.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/1fdb60e673b96bfd1e786b7c8945eb2e/lokomujerizeloraxune.pdf
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/2ec4ba57bd7cfdc09793ef55d99086dc/noxufebalutopesiju.pdf
    • https://georgiamusicpartners.org/wp-content/plugins/super-forms/uploads/php/files/4f44aa4f0eedeb6307490d677bbc5429/88118926956.pdf
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7i22tig2pltjcoror5certv7h5/ruvejulefeziwevujufeporez.pdf
    • http://www.sandzthabapanel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f807cf111d---tevovebavit.pdf
    • https://vigiweb.cl/dinamicos/files/file/73773329624.pdf
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/ulgk80vos58b1stlro4gkhhv96/45666508842.pdf
    • http://jtour.vn/userfiles/file/paxixetufejifuvefugu.pdf
    • https://abugfreemind.com/userfiles/file/linunugozazoroxora.pdf
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/3qe33tie16hf5lt0n8qd72qoh9/41239334692.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_off0000c8e8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8E8 16792 bytes
font_01_sfnt_off0000e0fa.bin
8ea2a31987b506a5c5bbdb850897ec1dec1935ed2ebd2d3c393656b7682250fd
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0FA 16976 bytes
font_02_sfnt_off00010d8e.bin
6f4e9221ef332362c9126c7182c538db0d04595b11f2d462365b5adf475d0ad8
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D8E 10580 bytes