Malicious PDF — malware analysis report

Static analysis result for SHA-256 33d517533363631a…

MALICIOUS

PDF

77.7 KB Created: 2021-09-04 00:14:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 98926a9f564e26a4e55c2bb75c987a28 SHA-1: 0da041b14058447ccb6571a9cccd072d24ec38bd SHA-256: 33d517533363631ae941b2cafc205db72870dd80bdc5a8ce61d32b9d37caf40c
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress sites, a common tactic for SEO poisoning and distributing malicious content. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of external links and a link farm structure. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic findings are sufficient to assess the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9943

Heuristics 5

  • 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://xn----7sbabak5acz7byau.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f3d4f96fb865dd10d7bf78d964d0dc80/xemas.pdf In PDF document text
    • http://climtech.com/files/files/biruwejus.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a59fbc778be---77293840358.pdfIn PDF document text
    • http://www.hydro-tg.pro/upload/file/54890723922.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/lotubelefugefemujigu.pdfIn PDF document text
    • https://sjalikave.hu/pictures/file/63421601087.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/p6foid2eaiep95iuqh6g2qa9ln/28539075324.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/7d7b159ae6ef0eaff7aa49209dba0159/xufoxukerujinugoraxuxireb.pdfIn PDF document text
    • https://ajitcoatings.com/uploads/puwupedumuwejofusob.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1608fae9713cc3---velagifewipu.pdfIn PDF document text
    • http://cattaneoarchitetti.it/userfiles/files/nokuwobolotesivilutet.pdfIn PDF document text
    • http://frankslawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/dodojifuxos.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1610099d1c3e61---vuwajofamoxexozo.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6069f758b2---fewijajiwujok.pdfIn PDF document text
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a96c6093619---pizajejud.pdfIn PDF document text
    • https://adikkedua.com/contents//files/nesitisafuvobibufasosuma.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/58793701261.pdfIn PDF document text
    • http://twinmd.ru/userfiles/file/puvufetomijagakevi.pdfIn PDF document text
    • https://flexi-cms.com/uploads/file/81635404047.pdfIn PDF document text
    • http://divodizain.ru/ckfinder/userfiles/files/13327198703.pdfIn PDF document text
    • http://lhsclassof68.com/clients/73441/File/verefojogexibuwoli.pdfIn PDF document text
    • http://atomleasing.ru/media/File/vupijiwufinaduvegapolon.pdfIn PDF document text
    • http://wideanglepackaging.com/ckfinder/userfiles/files/dekidagoxagizu.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab7d0151611---47001823245.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16126faca0438b---21324205562.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=solution+of+ordinary+differential+equation+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ca3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA3F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE256 10756 bytes
SHA-256: 29c1c52962a59786093180f2f5a28cd9cb697d88495173a375ae123c38ab207f
font_02_sfnt_off0000fafa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAFA 17644 bytes
SHA-256: e2d5ea73d51eeb7a52a767cbf6236be03ba837b8c634d5ba2c0523a7d29043d7

Open this report in the interactive analyzer, or submit your own file for analysis.