Malicious PDF — malware analysis report

Static analysis result for SHA-256 58b27d0db4d27b4c…

MALICIOUS

PDF

79.7 KB Created: 2021-09-17 09:42:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f937cedfc798a6553e4eec052e30fe97 SHA-1: 2b372cbcf9a8ffc1f6b2835ea6d7d7f727ca7ab4 SHA-256: 58b27d0db4d27b4c193c67112b7496fde37ef6118abb2e3119470acd205d5bd5
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous links, many of which point to compromised WordPress upload directories or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The presence of multiple PDF link farm heuristics reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://namngonviet.vn/user-/files/rufososupapupuzofatol.pdf
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613e68e6afd3d---popuraruzutix.pdf
    • http://tai-yang.tw/taiyang/upload/file/25627275412.pdf
    • http://17njl.com/userfiles/files/jubuvege.pdf
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133fa2f6e104---85337085179.pdf
    • http://autoscuolepintozzi.it/userfiles/files/53155322069.pdf
    • http://lecostationery.com/files/file/wetini.pdf
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea85f3809a---11297604733.pdf
    • http://tries.cz/media/images/upload/file/28175553642.pdf
    • http://sakem.org/userfiles/files/dadonomipokexuxatuwusutip.pdf
    • https://inprovitperu.com/ckfinder/userfiles/files/gedigamuzunis.pdf
    • http://kientam.info/uploads/userfiles/file/dujewibubokufo.pdf
    • https://namratalakhotia.com/userfiles/files/lobovifeniripebulaniv.pdf
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/15gf1cf81uvqn765uoavdc9ljf/27342912888.pdf
    • https://imaggu.com/ci/userfiles/files/11584897967.pdf
    • http://adirondackseafood.com/ckfinder/userfiles/files/97153357005.pdf
    • http://kochamsushi.pl/UserFiles/file/pafabiregupe.pdf
    • https://www.le-domaine-de-hauterive.fr/ckfinder/userfiles/files/gogukeduxomazuru.pdf
    • https://austarpharma.austarchina.com/upload/files/nirin.pdf
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/161428a57e4e27---11940024147.pdf
    • https://ihotel2b.com/upfiles/editor/files/tozidesubuwapivuzidepud.pdf
    • https://duhocblueocean.vn/ckfinder/userfiles/files/90847201207.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=gta+sa+gta+v+mod+apk
    • 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_off0000d4ed.bin
0d786e0f4f06d28ca832d366c7f8b41b73e26c14f020c2765a8e6a1849f0b6b7
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4ED 17384 bytes
font_01_sfnt_off0001021a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1021A 16792 bytes
font_02_sfnt_off00011a31.bin
2aea42e9d4b5776e224a8ae22dfa208e8858ca39b2b62a9a28409ef36d9408ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A31 10456 bytes