Malicious PDF — malware analysis report

Static analysis result for SHA-256 6db85b71b3873a0d…

MALICIOUS

PDF

67.1 KB Created: 2021-09-28 15:54:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5a5c93f47b494e83cef8cc27a92e6a52 SHA-1: b35218c0e04963924929b521266ac3bc563ea3f8 SHA-256: 6db85b71b3873a0defc9ac788add88d1c1a73bcff96fe1a08c63347d20a54126
176 Risk Score

Malware Insights

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

The PDF is identified as a phishing lure due to its structure, which consists primarily of an image and a click-outward action, typical of screenshot lures. It contains numerous links pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 67 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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 http://xedaphcm.com/luutru/files/guwelizabuda.pdf
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614c550228fb0---703524915.pdf
    • http://podiummoda.ru/userfiles/file/gaxanubuwe.pdf
    • http://konberdbio.com/upload/files/51830128658.pdf
    • https://ijpdua.com/contents/files/17223622621.pdf
    • http://euskararenginkana.eus/files/galeria/files/57056440859.pdf
    • http://carzip.biz/files/uploads/files/54513127610.pdf
    • http://homeshopeez.com/uploaded_files/userfiles/files/6851649741.pdf
    • http://etoprosto.ru/ckfinder/userfiles/files/budufuve.pdf
    • http://honderhotel.com/UploadFiles/FCKeditor/20210904013758.pdf
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16149f85599c6a---vakazepejokitimal.pdf
    • https://exlite.it/ckfinder/userfiles/files/67128642494.pdf
    • https://www.syria-report.com/sites/all/libraries/ckfinder/userfiles/files/jewemipoxuxutet.pdf
    • http://gamecoast.by/uploads/files/58647264121.pdf
    • http://enjoybowlramenandpoke.com/uploads/files/51455360629.pdf
    • http://dentalweek.eu/userfiles/files/nefotisixejiju.pdf
    • http://mrhobbscoffee.com/images/uploads/file/70940061669.pdf
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/1313eff71a3b32e5727aaac59fa8e483/roxesib.pdf
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/velakifutodige.pdf
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614034a554ef0---tutizenazamokosum.pdf
    • http://buyyoutubesubscribers.com/ci/userfiles/files/vilefoxolurumigexibidikug.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=transfer+all+data+from+android+to+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_off0000ac96.bin
2d0f6b243d4d53ff0b4c01f95fceaabe8e183e10208b1a19e5415668385efaae
pdf-font-stream PDF embedded font (sfnt) at offset 0xAC96 10476 bytes
font_01_sfnt_off0000c45b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC45B 16792 bytes
font_02_sfnt_off0000dc6d.bin
4eff151b804d91fdc128b96c327ccb008d3155fffbf0934c643d7f176aef3c05
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC6D 14108 bytes