Malicious PDF — malware analysis report

Static analysis result for SHA-256 35411c55d277fa2c…

MALICIOUS

PDF

83.4 KB Created: 2021-08-10 02:44:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 3b5a3b28f984a2a996ed227bf17f0878 SHA-1: d2c14c24e3e24e5276c10cb9340876f3a0e0a3d2 SHA-256: 35411c55d277fa2c99bd2b98e3b9799563a8565ae9da95460f9d26bdf5047b4a
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and other domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these external links. No scripts were extracted, and the document body was unreadable, but the heuristic firings clearly point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://frontlinetherapist.com/wp-content/plugins/super-forms/uploads/php/files/756d22c6cd92f2b14e37dcabc71edb47/60138036951.pdf In PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/53902775432.pdfIn PDF document text
    • http://richwoods1969.com/clients/861079/File/31598242266.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a68e9678d9---filagejuwuvugi.pdfIn PDF document text
    • http://packamate.com/userfiles/radagiruzudeboxo.pdfIn PDF document text
    • http://netinflux.net/userfiles/file/moxududimexotikiva.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/4335c15fd4a0cf90626d0940a16c9bf6/12607006515.pdfIn PDF document text
    • https://rybczewice.pl/userfiles/file/1071501606.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/kcmtqvnuef3k5lccl7i91etpo2/setusagukurijokem.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/890d04b73431046f993f201858223148/53004352991.pdfIn PDF document text
    • https://youstore21.com/wp-content/plugins/super-forms/uploads/php/files/c259b9bbe0039ef8459357589a8cede4/xijedepog.pdfIn PDF document text
    • http://biotop-zamosc.pl/userfiles/file/kabipowolugupimasulibur.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f71f4933038---51398685997.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607005ad22753---majizux.pdfIn PDF document text
    • https://perleyparish.org/wp-content/plugins/super-forms/uploads/php/files/52abc297cb040fe10b9db7b602de843f/kivitaze.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160dcda881e127---63142834376.pdfIn PDF document text
    • http://ty6600.com/userfiles/file/zomamezidewitufivewixa.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/0a763807531c82fdde56f14c78d9b22f/58648945006.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160ade71951304---71386559764.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608fa6aa96d99---nuxux.pdfIn PDF document text
    • https://mystruggle.uk/indigo/ckfinder/userfiles/files/84956793455.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b567d1cd318---51956012689.pdfIn PDF document text
    • https://pottoka.info/files/galeria/files/86716323564.pdfIn PDF document text
    • http://xn--80aamdqpfpr.xn--p1ai/upload_picture/57263812527.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=sumas+de+dos+cifras+para+ni%C3%B1osPDF 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_off0000dffe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFFE 11016 bytes
SHA-256: 1d0b0132d3995292d90af64445c5b8a2e6e3fc0d00a310b6a670f6a200d59a14
font_01_sfnt_off0000f942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF942 17616 bytes
SHA-256: 2ecaa496fa6abdfc530af08c0237c4d704405c1c95960e5b2e3e02dcee6c63f4
font_02_sfnt_off000125df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1