Malicious PDF — malware analysis report

Static analysis result for SHA-256 7849c41018a7c63f…

MALICIOUS

PDF

86.3 KB Created: 2021-07-14 09:16:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b688356a459786439c0205c2ed039c2d SHA-1: 7979eb6b4ab4b88478214cb18fdd67a8cbb83854 SHA-256: 7849c41018a7c63f068c09f6489c5c128ebe4eeca097fb5f621e6937267c6730
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to numerous distinct hosts, many of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to distribute further malware or engage in phishing. No scripts were extracted, but the structure and URL patterns suggest a malicious document delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 https://rubenoferro.com/userfiles/file/suwiparexijidupejejaga.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/251t7pk9uv6t8dujecpu88l6h2/kuxesevazilijuwologaniv.pdf
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160845a14018b7---39059268644.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/78390312000.pdf
    • http://jingchengs.com/jingchengs/ckfinder/files/20210708084954.pdf
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/34b3b8d8932833526c6a7e46f4e5c0de/laxirejorebiduwobawom.pdf
    • http://namthangbasaltstone.com/uploads/image/files/bixufex.pdf
    • http://dade666.com/userfiles/202106file/2021062020205270554.pdf
    • http://dejede.com/userfiles/file/30563217519.pdf
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/492321f8064ff636f754a0b525390bb5/39459692943.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609cc2e28f9fe---zixirikiviradojevided.pdf
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/sqvvig9b728gpk365av01acqhf/42668045218.pdf
    • http://palenice.net/obrazky_clanky/file/65094708913.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16083da6b73178---24285278507.pdf
    • https://sailstudy.in/ckfinder/userfiles/files/7462228453.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16076220d44f60---19816279002.pdf
    • http://alexlunacoach.com/img/editor/file/90426367102.pdf
    • http://generale-bureautique.fr/gdb/files/file/89817629661.pdf
    • http://zaun-produzent.de/userfiles/file/bifixiwelisaxapabam.pdf
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/d822e4a8d3ee97df83b54537a7ff8706/xopufak.pdf
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a06cd52d0c5---34563074810.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160b0d5ca499bb---21231070587.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=calories+in+1+air+fried+chicken+wing
    • 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_off0000edda.bin
51bc0c2bac0a45b43712404e85297c98a3419bf5edc105dbe5c4de3c74ef095f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEDDA 17212 bytes
font_01_sfnt_off00011a96.bin
406a83615294b8eea4aad574c95eecb809194e5da4c4defc71be967a0479bbc5
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A96 10916 bytes
font_02_sfnt_off000133ba.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x133BA 16792 bytes