Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c401fd9413befb5…

MALICIOUS

PDF

83.1 KB Created: 2021-09-06 09:49:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 23c154fb092579f5d9123270b7bb0189 SHA-1: 9f0d1e799a6c3b1286c88da2d5630e43d77a5f0a SHA-256: 0c401fd9413befb51d79efc690032777dc0c3fe6a2ecb4ba4940250cff43aae0
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier strongly indicated maliciousness, and several heuristics identified the PDF as a link farm pointing to compromised CMS uploads and disposable hosting. While no scripts were directly extracted, the structure and URL patterns suggest an attempt to lure users to external sites, likely for further exploitation or phishing. The presence of numerous URLs, many hosted on compromised or suspicious domains, supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://fusen-es.info/yamituki-n/uploads/files/89448059720.pdf
    • https://vyrukrc.lt/userfiles/file/newasovoxugowewigavasid.pdf
    • https://acgroupenterprise.com/userfiles/file/30388454268.pdf
    • https://www.birdandwildlifeteam.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085304341663---97054486777.pdf
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/6ad8e9e78409e3ff3f776f9381247245/56816372633.pdf
    • http://mrs-edu.com/sribati/editor/uploadfiles/fumaxeduzonorozobetonalek.pdf
    • http://austral-immo.com/userfiles/files/22929933778.pdf
    • http://hladonural.ru/upload_picture/maxidekenaviwosu.pdf
    • http://15881588.com/ckupload/files/46755559375.pdf
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/6a3323a48784986b1a349f3bf93a2769/wenapevolovivavalogizebif.pdf
    • http://nano-vip.com/ckfinder/userfiles/files/44642675549.pdf
    • http://helpibr.org/clients/f/fe/feaff840d005acecac0f151e8679c8db/File/80316265290.pdf
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607744530de55---mibojipa.pdf
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160c8aee915a2a---pezunesadumo.pdf
    • https://permargi.com/files/galeria/files/89623100124.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/souc3c3gmfubu8fl0grvtj2ti7/91106556314.pdf
    • http://dinskayarealty.ru/media/file/27647550144.pdf
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/b618a3a6557142040a1df81869af951b/dokugujazexamek.pdf
    • https://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/a59591254821f1b9a5484542b8e00641/kanolifodixov.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/60ac2dbd288072bd66c0867359c175fe/dufikufoxitudugejezepijem.pdf
    • http://vhshf.de/File/27146740849.pdf
    • http://dalaichau.com/files/bogebezifabediwul.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/2459d50961e9e2523ec0a4ae1831bbdd/96123193134.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2cc58ca242---32819567979.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=smilinguido+para+colorir+pdf
    • 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_off0000e0b1.bin
df35df93ba854935d175a70f7962fb233c667dc9971f6812010db42e77cb5ff4
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0B1 17512 bytes
font_01_sfnt_off00010e1a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E1A 16792 bytes
font_02_sfnt_off00012631.bin
6e4871707f4d9bbfeb42d94f06a519b96eaa014effd8a2bcd8def998d54cb76c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12631 10740 bytes