Malicious PDF — malware analysis report

Static analysis result for SHA-256 164657e6177b0948…

MALICIOUS

PDF

88.3 KB Created: 2021-09-17 22:58:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fb6841e989e0c0c0c427fb94929c6ea7 SHA-1: e4deb52a9abbde07320492d58b65cf550d1d07f5 SHA-256: 164657e6177b094848408b9d7f4115d8af96d4d9153a6a93e4c4ae0a9c23ea66
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to various domains, many of which are identified as disposable hosting or potentially compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://apisicul.com/userfiles/files/lomebewobugokosobilekez.pdf
    • http://k3projekt.pl/uploads/userfiles/files/norinixofumok.pdf
    • http://bjhtdszdh.com/v15/Upload/file/2021910239521161.pdf
    • https://www.ebenisterie-burette.com/ckfinder/userfiles/files/zogulur.pdf
    • http://balone.net/_upload/file///riximozurilidel.pdf
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/dfdc02833184afc1b97a2206610ce430/91348211978.pdf
    • https://kimcert.com/E/file/fezuxipugetasazidab.pdf
    • https://alperbehang.nl/userfiles/file/59602196931.pdf
    • http://daiichigroup.net/uploads/news_file/31267186324.pdf
    • https://pachetedeturism.ro/images/files/naxonifegot.pdf
    • http://dealershop.es/userfiles/file/fudazipumogufenuwimunalo.pdf
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/a69a0c6dc8a6f5a5eb830c90ca9ec626/61939404482.pdf
    • http://www.examnotice.in/uploads/files/60469126250.pdf
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/wenudoraf.pdf
    • https://dijitalsanat.link/upload/files/99693106781.pdf
    • https://hoangphatdanang.xetnghiemadndanang.com/uploads/image/files/mikifowefesokepadutumedu.pdf
    • http://quick-thailand.com/images/uploads/file/wuvoxetumaxetatamadug.pdf
    • http://rustproofingottawa.com/userfiles/file/62900414666.pdf
    • http://shiraz.sk/ckfinder/userfiles/files/jibutotuzavux.pdf
    • http://artgrafika.cz/userfiles/file/jadokuvidalum.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/161359ec241618---zegekisa.pdf
    • http://1-cities.com/blog_images/blog_/file/39020078945.pdf
    • https://valkexclusief.reviewz.eu/app/webroot/files/userfiles/files/1890101433.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=50+shades+of+gray+watch+online+for+free
    • 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_off0000f169.bin
be1154509c4691c8ea975ef0d628b25a051f9228eca9b5c98481f2cfb40fa156
pdf-font-stream PDF embedded font (sfnt) at offset 0xF169 18660 bytes
font_01_sfnt_off000121ca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121CA 16792 bytes
font_02_sfnt_off000139e1.bin
b16682d3ee53d785a54662ba14531b47078787a0050d00177fcab0703ba1f778
pdf-font-stream PDF embedded font (sfnt) at offset 0x139E1 11116 bytes