Malicious PDF — malware analysis report

Static analysis result for SHA-256 764f8c771b370bfe…

MALICIOUS

PDF

69.1 KB Created: 2021-09-30 11:38:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6505862268bf7031ac482b5361fcc346 SHA-1: 2af0e8daa79a954c34ab7eddc9cbf0e2cc05f460 SHA-256: 764f8c771b370bfe355dacead730b7365d44542bdee3bb63b6523f7d31a8f222
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised CMS upload storage, with numerous links pointing to disposable hosting. The embedded URLs suggest an attempt to redirect users to potentially harmful content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16155731debf36---45742851555.pdf
    • http://dkind.net/userData/board/file/19489448458.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/8554ce1a3ea937639a14bd4f31fcb1cf/puvaliber.pdf
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614189ffbff07---pujamanovunusubamamusiw.pdf
    • http://www.azurwelcomeservices.com/userfiles/file/66249361483.pdf
    • https://h1t-urlaurora1-turbo.com/contents/files/bafutebuwidopavufozoji.pdf
    • http://ablerexthailand.com/userfiles/files/velekofegawep.pdf
    • http://pwr-tech.ru/userfiles/file/wilewewivarifur.pdf
    • http://ewtch.com/upload/files/mufiwutaroxa.pdf
    • http://henanshuangxin.com/d/files/40871390284.pdf
    • https://bselink.com/userfiles/file/41044346167.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16131f7636451d---kasanogi.pdf
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/68249392363.pdf
    • http://sevenseahotel.com/uploads/images/files/79944961964.pdf
    • https://dom4m.by/userfiles/files/7247116924.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/v7tvg4kqti1bc4f101f92icpul/fapuramitokigofu.pdf
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/ed16d1c1269d855918f264cdfbf65b01/72717724070.pdf
    • https://www.hosotte.com/ckfinder/userfiles/files/12053902740.pdf
    • https://jamuiboe.com/webroot/upload_media/33728057442.pdf
    • http://xn--djr00fsyfv0o5qgy9u.net/filespath/files/20210911144731.pdf
    • http://taeguektour.com/FileData/ckfinder/files/20210911_342F391016938102.pdf
    • https://advantage.ee/media/contents/file/tupofo.pdf
    • http://podwierzba.eu/ckfinder/userfiles/files/zadixasebugukerarijojusav.pdf
    • http://muabannhagiare.net/images/uploads/files/babapurutoledubigarijudas.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=anybooks+paid+version+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_off0000b06f.bin
7ea64616674508128125de1e73e4fdd0db2ae8fdce7cee775419ae37352e118f
pdf-font-stream PDF embedded font (sfnt) at offset 0xB06F 10636 bytes
font_01_sfnt_off0000c8bc.bin
00dff0b5010d9b470bcdebced122af1f69715f5386e2189cde466ac764b3724c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8BC 15204 bytes
font_02_sfnt_off0000eed6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEED6 16792 bytes