Malicious PDF — malware analysis report

Static analysis result for SHA-256 44443d6eeb5ebe11…

MALICIOUS

PDF

81.3 KB Created: 2021-08-23 18:36:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 770b6b5c1b1af11318763ecf56cfcd9e SHA-1: c989a97aa61f01133d78dead8a27c0ccac1b057c SHA-256: 44443d6eeb5ebe1170d7ea785c163d64fb6cff8303aac4a2b705e7e042a83e35
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. It contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised WordPress sites acting as link farms. The primary purpose appears to be directing users to malicious or phishing websites, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://laborke.ru/uplcv?utm_term=pain+in+left+shoulder+and+neck
    • http://perfekttorun.pl/pliki/83838758775.pdf
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/9jvoag5s5vn251u2vmqbl878fc/mizekopo.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077c7712cda1---pifudurisata.pdf
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/4ac9eaa72f33524c1036662887934a4d/vusupejapidusov.pdf
    • https://cursosgratuitosonline.es/wp-content/plugins/super-forms/uploads/php/files/8tjkor6tdq7dfor1rd4hq381ue/tozim.pdf
    • https://2acontractor.it/images/file/37115642248.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/35825638fbb1d4c06dbfe7ab1d9aa6b2/17776818284.pdf
    • http://drthchowdary.net/userfiles/file/potuzuvomepizurixagege.pdf
    • https://www.vek-bg.com/app/templates/js/ckfinder/userfiles/files/toruzalelaxire.pdf
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/923626cc432a2440cc3fb2c4b90c59b2/1915835633.pdf
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160839067894b4---jamirolobumotifan.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090db4d81d7a---82129742486.pdf
    • https://globalclassic.org/wp-content/plugins/super-forms/uploads/php/files/7eqo2aqv81cc6qnrubggf8nq1v/15996922783.pdf
    • http://charivne.info/images/file/lepuzubuju.pdf
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdd687a04dd---pewanokeb.pdf
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/373b6aa534f2a709f919d73c7a605999/94701568464.pdf
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d54a7b21d6b---vafebiporejobirefaw.pdf
    • http://www.icareonline.net.au/ckfinder/icare/files/26822637522.pdf
    • http://warraichmeats.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607046c80ee46---nexisobotigogufitikusoti.pdf
    • http://abwingsva.com/uploads/files/fepixa.pdf
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160781f11e658b---79495224297.pdf
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/8mi4648nms42n8lor4hgblobtm/pefogesisug.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_off0000dd57.bin
8ff42f395e7de4d4f997c4542a1a3a98337a444bf13c4a2af80881c1e22c3564
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD57 10768 bytes
font_01_sfnt_off0000f60d.bin
55b1ca81c21c425b8acc252bf9b4620f34d8532db310769f132d28fd3f5e6866
pdf-font-stream PDF embedded font (sfnt) at offset 0xF60D 15932 bytes
font_02_sfnt_off00011f38.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F38 16792 bytes