Malicious PDF — malware analysis report

Static analysis result for SHA-256 52af9000a5d2bb88…

MALICIOUS

PDF

93.2 KB Created: 2021-09-22 11:55:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3d20e9a4b65ff2a51ccb876c82d4623a SHA-1: 75cf45a9a9381c8a59fc0abebac618116ccc917c SHA-256: 52af9000a5d2bb883d33f9a2586b242dbfb6aa7e8c27b0a354a7e0431deea53d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to websites hosted on compromised CMS platforms or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://olterus.info/contents/files/juruvivuguvoxopirivowumod.pdf
    • https://s-serviss.lv/userfiles/file/givukixegumovep.pdf
    • http://colegiosantarosa.com/uploads/imagem/file/zadakelijogimuwifadinelu.pdf
    • http://slmj8.com/data/userfiles/files/xugadagezujelopanijeganek.pdf
    • http://barrybusiness-crm.com/ressource/devis-photo/files/gusibepuwulidoxuzizag.pdf
    • http://aiswaryamatrimonials.com/fck_uploads/file/wotuzegosefini.pdf
    • http://nuovojob.com/userfiles/files/busogakiwenem.pdf
    • http://indagosrl.it/userfiles/files/14617854282.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/fb9a4a71599ac07d88a3f1b4ee54d9a1/baxakuvikekak.pdf
    • http://worksafeorg.com/wp-content/plugins/super-forms/uploads/php/files/s11dbjv8u6mcei184rjah76587/mufowaxegus.pdf
    • http://rigosarchitects.gr/userfiles/file/kufogesikepiwe.pdf
    • http://bwlpsalisbury.com/uploads/files/pereg.pdf
    • http://gaudi.tw/upload/files/88254807985.pdf
    • http://shacklefordlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/52097575721.pdf
    • http://stimatacasa.eu/userfiles/files/58865786970.pdf
    • http://gewoongroen.eu/app/webroot/files/userfiles/files/86871013566.pdf
    • http://diagnosticaedilizia.com/userfiles/files/jimoguximamo.pdf
    • https://pikhospital.com/ck_uploads/uploads/files/gasujalivolumul.pdf
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/tmp/48673337942.pdf
    • http://lawngo.net/fckfiles/xevavo.pdf
    • https://diphong.com/uploads/76928860392.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/3c259ae467ff040fe5f1c626d0865413/5767287536.pdf
    • http://language-coach.pl/uploads/files/88656699317.pdf
    • http://xn--80aatg4aaaddkhfhbf3evf.xn--p1ai/ckfinder/userfiles/files/tetalexajomolosokale.pdf
    • http://sxcec.org/userfiles/file/nomomijujavorom.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=best+websites+to+watch+free+football
    • 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_off00010967.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10967 16792 bytes
font_01_sfnt_off00012179.bin
cfe1458f5f57236d4f960ae85cadc4e9d4aef701e58123b5efc1680354d14c90
pdf-font-stream PDF embedded font (sfnt) at offset 0x12179 17544 bytes
font_02_sfnt_off00014e82.bin
deb2408b43f7d5fb063fcb687df3a1a81b12f0fb38d4574061c8ffe941efcbfd
pdf-font-stream PDF embedded font (sfnt) at offset 0x14E82 10608 bytes