Malicious PDF — malware analysis report

Static analysis result for SHA-256 0f5cd56264f7585e…

MALICIOUS

PDF

85.9 KB Created: 2021-09-16 20:55:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 638773b1823cffd4101b944d16bb8570 SHA-1: 004fc4cfe7cbe102d928f761824d763331740fd6 SHA-256: 0f5cd56264f7585e14d42201adcf37fee66dc801a96375db0b3a0552711b7d2a
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier strongly flagged this PDF as malicious. The primary attack pattern observed is the use of a link farm, potentially to distribute malware or engage in SEO abuse, with specific links found on compromised WordPress and other CMS platforms.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • 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://www.otevrenysklep.cz/ckfinder/userfiles/files/pikigifesal.pdf In PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/fg21fu9r3ac1ltc5i7t9ea3217/97131779704.pdfIn PDF document text
    • http://website-design-company.in/dev3/damodar/ckfinder/core/connector/php/userfiles/files/zedaxonusapere.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/lolazasaxageba.pdfIn PDF document text
    • http://thietbiotovn.com/Images_upload/files/81664451562.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613112fa871a7---pugulu.pdfIn PDF document text
    • https://postelezmasivu-praha.cz/ckfinder/userfiles/files/bomidisusujed.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16135caddb2975---vujuxunodugewunux.pdfIn PDF document text
    • http://savvyais.com/userfiles/file/86260224583.pdfIn PDF document text
    • http://bandenplaats.nl/cmsimages/file/57429414492.pdfIn PDF document text
    • http://pereplanirovkaoblast.ru/pict/file/funujepoxizuweluzeganek.pdfIn PDF document text
    • http://www.motocams.cz/ckfinder/userfiles/files/14210137172.pdfIn PDF document text
    • http://babywagen24.de/userfiles/file/44604103568.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16131506a3e469---jojiboteriwobideruwu.pdfIn PDF document text
    • https://kiofruits.com/admin/uploads/files/788394388.pdfIn PDF document text
    • http://studioscoponi.eu/userfiles/files/puduled.pdfIn PDF document text
    • https://we-plus.tw/ckfinder/userfiles/files/wejorade.pdfIn PDF document text
    • http://sinojjacob.com/userfiles/file/fodozazokaxepu.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-12/20210912223600509731.pdfIn PDF document text
    • http://ropesadventure.com/d/files/57066188241.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132493e5fe38---modupedukapaxedejajijuw.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/29178767443.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=iptv+smarters+pro+apk+androidPDF 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_off0000e06c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE06C 10616 bytes
SHA-256: 5e46fdf7e97b378edb0d6e79a5db4fb992f431324d3176172468df01bf50ad85
font_01_sfnt_off0000f8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B8 21792 bytes
SHA-256: 9964760921527fbc17dc7baae1a40f4a727e74c7041c0ed2ad0ceab9096f476e
font_02_sfnt_off00013233.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13233 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1