Malicious PDF — malware analysis report

Static analysis result for SHA-256 a79437c6affcd545…

MALICIOUS

PDF

81.8 KB Created: 2021-09-14 13:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a73118f5c397f65bb508e9111fe131bd SHA-1: fba3c385cee5c3f7bb47f84c804ebf8c12bb55f0 SHA-256: a79437c6affcd545bdf3a24cdb30421ddaf70e1261f2dc64ea5bcf2f8281060d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of a link farm hosted on disposable or compromised domains. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were directly extracted, the structure and URL patterns suggest the document is designed to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://garglob.ru/uplcv?utm_term=puffin+pro+apk+ios
    • http://skrutit-probeg.ru/upload_picture/file/wunelojog.pdf
    • https://rtvpuls.com/ckfinder/userfiles/files/35538244323.pdf
    • https://777mto.org/contents/files/29237020696.pdf
    • http://greenmodels.ru/uploads/files/85662473838.pdf
    • https://fallahi-sch.com/userfiles/file/83852173144.pdf
    • http://huspanda.com/data/ckfinder/files/vezapumixikevumuminit.pdf
    • https://onutglen.com/caningest/images/file/kaberajajav.pdf
    • http://k9careclinic.in/ckeditor/ckfinder/userfiles/files/zopov.pdf
    • http://arunimaflavours.com/userfiles/file/ruxiwawosu.pdf
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135e09c75e7f---56361237179.pdf
    • http://leinerpakgelatine.com/survey/userfiles/files/sadimejasuno.pdf
    • https://almavilag.hu/files/files/zowizoxebav.pdf
    • https://gymlesgeants.com/upload/editor/file/21711444734.pdf
    • http://ahkkpcm.org/userfiles/nukunutodepubudipereg.pdf
    • http://behtarinekhodetbash.com/files/files/63070864690.pdf
    • https://coverline.ro/userfiles/file/betanutulajemovo.pdf
    • https://www.mds-horizons.com/upload/files/jowisoneruporufol.pdf
    • http://digilit.ir/basefile/digilitir/files/panumaxepazunijerasosavu.pdf
    • http://www.champcaregivers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3ed678712---galigugamola.pdf
    • https://webkapper.nl/ckfinder/userfiles/files/7268031030.pdf
    • http://kantipursecurity.com/userfiles/file/9740633498.pdf
    • https://kodcomputers.ro/2664/uploads/josodofenepowel.pdf
    • https://dongciao.com/uploads/files/202109131747074179.pdf
    • http://wang023spa.com/userfiles/202109file/2021091205110470554.pdf
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613fd6c4042e2---47204658956.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_off0000de43.bin
33292c1e251b0384f46dcafcf51fdc63e55ca82479332ae4dbf41c34fa49f4fd
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE43 17012 bytes
font_01_sfnt_off00010a0e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A0E 16792 bytes
font_02_sfnt_off00012225.bin
4677dbd1ab529a21168401731d97181064dd447f0655d955f940c4b82041e523
pdf-font-stream PDF embedded font (sfnt) at offset 0x12225 10268 bytes