Malicious PDF — malware analysis report

Static analysis result for SHA-256 13c9c70dfbefb89e…

MALICIOUS

PDF

87.1 KB Created: 2021-07-16 08:38:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 80710174c6b1857ca507376ee7e59d0e SHA-1: 07c818ef136620389775e55a4132015da9454c96 SHA-256: 13c9c70dfbefb89e195300d90462d16f26949904c28a856cb93aad1f7975dc1f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF was flagged by multiple heuristics and ClamAV as malicious, specifically as a phishing trojan. It functions as a link farm, containing numerous URLs pointing to compromised WordPress sites and other domains, likely intended to redirect users to malicious content or phishing pages. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=2d+driving+games
    • http://www.agenbenangbandung.net/file/9300513985.pdf
    • https://artlabjo.com/userfiles/file/6703993248.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160af8fcb555b3---33500464258.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1607739fa46d2e---91737407821.pdf
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/ddd06c89580d289967786aa870396a97/xepatitezorefetivowuf.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840ebb3c517---13087314425.pdf
    • http://hoaisonland.vn/upload/files/53807102839.pdf
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160949152b7e0b---1947919926.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077b0bedf98e---32626284126.pdf
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081f954903b4---zuwolunuzalo.pdf
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/160945f24c91ac---91772377027.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e2d0fde3f22---vusivodupibefojemojurived.pdf
    • http://tcihk.com/userfiles/84024556270.pdf
    • http://hainescentreasia.com/images/file/dotadinebaxoz.pdf
    • http://geostudio.eu/userfiles/files/jufukesaseladezepilet.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/0d102fb38ee6181fc4f22794a277f33a/49466750245.pdf
    • http://cementfeet.com/userfiles/file/gepakujikako.pdf
    • http://akcjonariusz.com/UserFiles/file/28668023027.pdf
    • https://tlproduct.com/userfiles/file/47337378015.pdf
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/4uqa6aopajtkj705f73h2qq7o9/85315053668.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160738f85489dc---10112304781.pdf
    • http://vlajamo.cz/images/file/dawumajuruxefapoxifuwek.pdf
    • http://petersonspann.com/clients/3/32/32c4b2f41fa698b5b938e848169c8dcb/File/11789795080.pdf
    • http://westernmaki.com/uploads/files/7692219721.pdf
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/7b5b8a68b908535b5366a095985bb533/24850882231.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_off0000eff7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEFF7 16792 bytes
font_01_sfnt_off00010809.bin
d3762ea3646c18fdbc05655d450f8f50fdbf188d33afcb3d757471bf4094e530
pdf-font-stream PDF embedded font (sfnt) at offset 0x10809 18164 bytes
font_02_sfnt_off00013821.bin
75577312ec32eef4625b682f8925fcc6105b328aec76f9e5a5c70ecf13048472
pdf-font-stream PDF embedded font (sfnt) at offset 0x13821 10416 bytes