Malicious PDF — malware analysis report

Static analysis result for SHA-256 37aa42382a76a1b4…

MALICIOUS

PDF

82.3 KB Created: 2021-09-17 23:05:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 824941cb28d0b607d0b6e2bd0a6129dd SHA-1: ad185c2903528136a9e03bf23ba1068f0f7e4c10 SHA-256: 37aa42382a76a1b4c6e7f63194a68c973317abab32a6e101cde9bbae90e134be
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it's a link farm pointing to compromised WordPress uploads and disposable hosting. The presence of embedded URLs and the nature of the heuristics suggest an attempt to direct users to malicious sites, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://hgb.se/filer/file/vatulizizifore.pdf
    • https://mtmhomeschool4art.com/mycms/uploadedimages/editorUploadedImages/file/gijur.pdf
    • https://perfecthospitals.org/FCKeditor/file/lijuwob.pdf
    • http://eros-arena.name/eros/userfiles/file/9635415713.pdf
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/ef16deefb68e30fc1ac6b4ef7b7b0850/15722930765.pdf
    • http://www.eatvirukai.lt/uploads/files/35581480726.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613090d4bc780---setobegufa.pdf
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/a58699dccfda04d42078e3b9a1ff2065/bujutezamemapixe.pdf
    • http://lookkorea.net/userfiles/file/72254317438.pdf
    • https://tennis94.fr/img/pics/files/76080811525.pdf
    • http://xhzhengli.com/upload/56542486715.pdf
    • http://zhizhencn.com/filespath/files/20210917014934.pdf
    • http://brunagabriele.it/userfiles/files/zinonedonubobubomevupom.pdf
    • https://al-farh-iq.com/upload/userfiles/file/31037770716.pdf
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/89bac1c421e76b32400821cf51b30a1f/20887063994.pdf
    • https://grahampropertytax.com/wp-content/plugins/super-forms/uploads/php/files/f6394bdc49e90c190488c0403f17a7e7/35228400613.pdf
    • http://www.galiantsolutions.com/emailimages/file/43060621938.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/5ea9df79aa8b222bbf6dd09ae62ced63/53192769105.pdf
    • http://ggmtc.net/userfiles/files/81337693992.pdf
    • http://dichvuhangngay.vn/uploads/image/files/wezonujebubulosawir.pdf
    • http://ebd.su/UFD/7623/files/gavifubipozisajuwuba.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/5b6817df4daa2a92b61c50f28444a9ce/48221745885.pdf
    • https://sieuthimaytinhcu.vn/upload/files/rejiwepirutesosegilowosi.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=installer+applications+android
    • 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_off0000df25.bin
23e12d64c942587ddeaebcfa6379f0b3d0521b54e04006da367b501de6c67a91
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF25 17180 bytes
font_01_sfnt_off00010b2d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B2D 16792 bytes
font_02_sfnt_off00012344.bin
5ffa313dd61bcee507f4a996b460d8e34a32013862a6397313af3ed8f098f5f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x12344 10456 bytes