Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bf3c6df54671a67…

MALICIOUS

PDF

75.5 KB Created: 2021-09-12 12:08:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 81f72d4a6fc9ee82131c2735b3f87085 SHA-1: 37c10d71ed6a7f04ea09e46ada749f9e3e7a2bab SHA-256: 4bf3c6df54671a67d14d0b23ff64d6ad10a3aeec366909e99e84f1dccb46e274
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged as malicious by an ML classifier. It contains numerous embedded URLs, with one heuristic identifying it as a link farm on disposable hosting. The document body is heavily obfuscated, preventing a clear understanding of its specific lure. The presence of multiple external URIs suggests an attempt to redirect the user to potentially malicious content or for SEO manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

Heuristics 4

  • 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://vistobrasil.net/uploads/file/57640883450.pdf
    • http://spostojow.pl/userfiles/file/zenupusefuzititetaba.pdf
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/demugugirizikupakebib.pdf
    • https://betsin.org/userfiles/files/folofud.pdf
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/161396299ca7b3---41974016447.pdf
    • http://sovaimm.it/userfiles/files/90336671227.pdf
    • https://ibrahimkoc.com/images/Media/files/74616171054.pdf
    • https://artistprasanna.com/userfiles/file/3974945254.pdf
    • https://llibreriaha.com/img/events/file/fezovopofizog.pdf
    • http://studioassociatoemc.com/userfiles/files/vawufipekumabuzuwukegu.pdf
    • https://tectrongim.com/uploads/files/kesoxeguxizomore.pdf
    • http://showdoimovel.com/files/files/rekakupon.pdf
    • https://skopjemuzikon.pmgrecordings.com/ckfinder/userfiles/files/dexutijiseluxagikupozaboj.pdf
    • http://www.valaisconsulting.ch/file/57286641409.pdf
    • http://himalayakebab.com/shipinc/userfiles/files/64320077723.pdf
    • http://sarigol.kr/userData/ebizro_board/file/35780549323.pdf
    • http://intersonik.eu/upload/files/14197403340.pdf
    • http://ecompletecontact.com/ckfinder/userfiles/files/52043175395.pdf
    • http://thesei.com/
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/65885181501.pdf
    • http://saxonrt.hu/img/userfiles/files/21812862292.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=pixel+turn+off+live+caption
    • 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_off0000c413.bin
9c67f5e23d9045bd24ee850cfe886cf73b2b1d2af434a019c4c662fb12885926		 pdf-font-stream PDF embedded font (sfnt) at offset 0xC413 17132 bytes
font_01_sfnt_off0000f05b.bin
955083fa8a2ca34983a12570d403f8a6fc25b552e77335e8a14df3d1a8a31f31		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF05B 10572 bytes
font_02_sfnt_off000108a6.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1		 pdf-font-stream PDF embedded font (sfnt) at offset 0x108A6 16792 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.