Malicious PDF — malware analysis report

Static analysis result for SHA-256 fffbef41b5f5c7cc…

MALICIOUS

PDF

83.3 KB Created: 2021-09-20 02:08:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4269fb81963a19b359e0d00fc0de909d SHA-1: 33460b7a7e6957c04ec9a63fa13ac3eb7e5a9241 SHA-256: fffbef41b5f5c7cc4e199da5afd5bc574f37de79907e18473ebc7e766af0a75d
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 compromised CMS uploads or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery through these links. The presence of a link farm and the nature of the URLs suggest the document's purpose is to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://ktcyy.com/ckfinder/userfiles/files/ropesogadib.pdf In PDF document text
    • https://www.milestonesmn.org/ckfinder/userfiles/files/mezibazumafejevevefus.pdfIn PDF document text
    • http://adidravidar.com/ckfinder/userfiles/files/xagawitoxifakodalugom.pdfIn PDF document text
    • http://dynamic1984.com/user_file/file/99136439577.pdfIn PDF document text
    • http://phulieumaymacbaoco.com/hinhanh_fckeditor/file/xikimipibozamewibusafaja.pdfIn PDF document text
    • https://castilloexterior.net/ckfinder/userfiles/files/gisifofow.pdfIn PDF document text
    • https://toscanafantastica.com/userfiles/file/munizafipovisinupi.pdfIn PDF document text
    • https://www.poolsrus.com.au/application/third_party/ckfinder/userfiles/files/nutapunavuzebavurabek.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130940975ec0---2241095328.pdfIn PDF document text
    • http://lacasedescaraibes.fr/file/10723545577.pdfIn PDF document text
    • https://grdr.org/paidel/ckfinder/userfiles/files/resudelulewumupiwapu.pdfIn PDF document text
    • http://maiodi.com/userfiles/files/fevipigov.pdfIn PDF document text
    • http://ceresasrl.it/userfiles/files/2563544830.pdfIn PDF document text
    • http://dui-antidote.com/images/userfiles/file/fobekejiwe.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/28760278950.pdfIn PDF document text
    • https://cobaltinc.org/userfiles/file/ruzativarujisafilesipuji.pdfIn PDF document text
    • http://studiofagiani.eu/userfiles/files/zavesonemotezi.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/161315500d7ac5---47942757998.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/e0kvanbk3q5c9e2oaj4t2qp6l2/wosozavuxozotipat.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613ffa3849df3---satupiji.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/2039435411.pdfIn PDF document text
    • https://henuopack.com/d/files/86187052730.pdfIn PDF document text
    • https://adikketiga.com/contents/files/rinaluxivaxele.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/mevatodabizajilipotatin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+unlock+android+phone+if+forgot+pinPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000deb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB6 18396 bytes
SHA-256: 2008a498b9705a6d0179240d41612cfb7b59b82c8bdb5e3aaa12fd2bde27d0ae
font_01_sfnt_off00010e32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012649.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12649 11000 bytes
SHA-256: a1aaca50301f5dcedbb0b762cdec8f79e7110b3be811fddcdafe5ee87931fa4b