Malicious PDF — malware analysis report

Static analysis result for SHA-256 2e41e107f5862fa0…

MALICIOUS

PDF

80.4 KB Created: 2021-09-22 18:46:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f6e34a929e1cd9d0f33fc00e31718b41 SHA-1: e56c5d877598f4cfc50d3414882d48aa50e4c0f1 SHA-256: 2e41e107f5862fa0723a87ba4be18a193ee2da26927203f77af33fc8fbdda446
96 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs that point to other PDF files hosted on various domains. Heuristics indicate these are part of a link farm, potentially for SEO poisoning or to distribute malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent. No scripts were extracted, and the document body was unreadable, limiting further analysis of specific payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 https://huntic.ru/uplcv?utm_term=how+to+restart+moto+g3+when+hanged PDF link annotation
    • https://tigapilar.com/upload/files/gazujufaligazixudus.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/jupam.pdfIn PDF document text
    • https://indolabtek.com/Uploads/userfiles/files/kulufafupobevekurega.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/wuwatudolilajafunerav.pdfIn PDF document text
    • http://www.emploi.nat.tn/ckeditor/ckfinder/userfiles/files/84764571267.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/32977227923.pdfIn PDF document text
    • http://fresh-j.info/images/uploadedimages/file/wilotakevulapufixokipase.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/22127307730.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/saxonekurixukividen.pdfIn PDF document text
    • http://basaritarim.net/admin/editor_resim/file/42303258228.pdfIn PDF document text
    • http://slxiang.com/v15/Upload/file/20219181657466126.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/vifuwirasawelowobujum.pdfIn PDF document text
    • https://milorem-service.ru/userfiles/file/65348686940.pdfIn PDF document text
    • http://ominocoibaffi.it/userfiles/files/42980315444.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133d44f0811a---55308992298.pdfIn PDF document text
    • https://tefen67.com/userfiles/files/28182546133.pdfIn PDF document text
    • http://bociany.sk/media/file/30219965398.pdfIn PDF document text
    • https://gangwontaxi.com/FileData/ckfinder/files/20210904_069421830FF0EB88.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/cc6a2cf3d482b584196cd5bfe41f6ea7/7915204287.pdfIn PDF document text
    • http://dj-maily.com/uploads/pages/files/53296561707.pdfIn PDF document text
    • https://phukienbep.net/media/files/92552585343.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16144069ebe835---62636641863.pdfIn PDF document text
    • http://ivelinabozilova.com/userfiles/file/35002304721.pdfIn PDF document text
    • https://morganmethod.tuesdaytrader.com/ci/userfiles/files/37804073880.pdfIn PDF document text
    • http://vodnik48.ru/content/file/23811761979.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1613785bc3b079---kowexaramomopob.pdfIn PDF document text
    • 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_off0000d5c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5C8 10808 bytes
SHA-256: 6f4f7b4107e9c3c3feffe2192a373699580e6a533b8b9fbb9eb8b2955b902a10
font_01_sfnt_off0000ee6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001067e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1067E 17236 bytes
SHA-256: cbb5c96ce1640439475c5b35708819ba7822ea5d222ec263f55a1c00b85b088b