Malicious PDF — malware analysis report

Static analysis result for SHA-256 d35e31af9e0be4b7…

MALICIOUS

PDF

99.2 KB Created: 2021-06-30 23:14:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c57b84bcb680ca21cf7dd5ae1d91c04f SHA-1: 1913ffd08b57093edbcee054b0c0ec824a4b2f05 SHA-256: d35e31af9e0be4b7e69e5fe72bc47475dade5d2cbf4a060f4b1c69cf260dd378
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the heuristic firings clearly indicate the document's purpose is to leverage external malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://crewmak.ru/uplcv?utm_term=doberman+pinscher+mixed+with+chihuahua
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eac3d78bc1---9596053125.pdf
    • https://www.arphplumbing.co.uk/wp-content/plugins/super-forms/uploads/php/files/0cdhgk0uj4u3qduos35m0tqn52/55068635568.pdf
    • http://aberdeeneyes.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609afb40a72d2---turipububusedazidefibem.pdf
    • http://maidnheaven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a216bd68d08---99610726685.pdf
    • http://richmore.kr/uploadfile/fckeditor/file/ginorizabiduli.pdf
    • http://lycee-elm.org/userfiles/file/woruzimepok.pdf
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5043160858---52156723761.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab94e3815d5---68540266559.pdf
    • http://www.cerel.eu/images/wyswig_images/file/zikozofefenasukox.pdf
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160a4272c2bad1---depelakilalokaf.pdf
    • http://botosani.ro/img/uploads/file/jebujejosijatanojokukurun.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077494311e78---pofogaki.pdf
    • http://wsp.pl/userfiles/file/61634357631.pdf
    • http://belst.by/upload/file/40132215447.pdf
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095000c05552---domozarowuveze.pdf
    • https://zlatartopalovic.rs//files/febawedapamagodunonu.pdf
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a82a02b5ce1---54916829805.pdf
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095388d84dcf---40151021057.pdf
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096afbfcefb9---24596348740.pdf
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbe982977a---19202294119.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609498617677c---lomujidopufapuwiwape.pdf
    • http://vds-construct.pl/userfiles/file/98558660943.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607079185e5d9---vizeguw.pdf
    • http://perfecturology.cafe24.com/upload/editor/imagefile/bewunimopoxokibilopagadux.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_off0001206d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1206D 16792 bytes
font_01_sfnt_off0001387f.bin
e7bc8ee729d43c43e3cd00afc619baaaa3d889406643d3b275a4370e7ab92539
pdf-font-stream PDF embedded font (sfnt) at offset 0x1387F 17400 bytes
font_02_sfnt_off000165a2.bin
643be0509208fdccedf71b75e1f7c571cd184432be6128bed686059ef4ee5f32
pdf-font-stream PDF embedded font (sfnt) at offset 0x165A2 11164 bytes