Malicious PDF — malware analysis report

Static analysis result for SHA-256 41ea92b57edc24d1…

MALICIOUS

PDF

76.3 KB Created: 2021-09-10 03:44:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f598952390940853e013347a6b348df9 SHA-1: 55bd707e20b71b6fd7d3250e2b548a3e54f7c39c SHA-256: 41ea92b57edc24d186bc67abc3f8fe0f34dd15ddd8aa1dd289d181eecdfbcc3b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm structure, suggesting an attempt to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16135c85236e59---xosekojaxageles.pdf
    • http://www.derbysignandgraphics.com/uploads/file/webasugisogufur.pdf
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613727ed811a7---gexotavuti.pdf
    • http://vngo-cc.vn/cooker/public/files/pekisowibadunolex.pdf
    • http://gzmingjun.com/uploadfile/files/20210909_083255.pdf
    • http://roycraft.ca/userfiles/file/debaf.pdf
    • https://digireg.nu/upload/36947385547.pdf
    • https://spotiverify.com/ci/userfiles/files/jugam.pdf
    • http://spbmedaks.ru/sites/default/files/uploads/80158784698.pdf
    • https://takipcisec.com/calisma2/files/uploads/41601729604.pdf
    • https://booburger.myagenda.cz/pictures/editor/files/67088209799.pdf
    • http://elai.kz/upload/2021/09files/210910011622090197vbubb.pdf
    • http://badgerhillfarm.uk/69451512133.pdf
    • http://sorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/47560376633.pdf
    • http://macro-e.com/app/webroot/userfiles/files/jobesekuzebakigitizalina.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/82970d2c8f0cc0aa389db21272262216/86180338626.pdf
    • http://fine-cottage.ru/userfiles/file/xalane.pdf
    • http://tehpromyar.ru/media/file/nufulusikugipudotisu.pdf
    • http://tgtech-auto.com/userfiles/file/26514942761.pdf
    • https://travelworld.ro/userfiles/file/gawukefo.pdf
    • http://aibasylhet.edu.bd/app/webroot/ckfinder/userfiles/files/77827251583.pdf
    • http://civicwomen.com/ckfiles/files/pumox.pdf
    • https://hlj-vibration.com/uploads/image/20210904/files/20210904101057.pdf
    • http://frankifoto.com/uploads/pages/files/wadigirutorar.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=mxq+pro+4k+5g+hard+reset
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b095.bin
e20f1319638ac6d62e038bfb61794e41c6722a1afaf37180ebac22a32562fdb7
pdf-font-stream PDF embedded font (sfnt) at offset 0xB095 16380 bytes
font_01_sfnt_off0000c729.bin
94cbc646b614a2068003aac11420447a7703808ef713c759efc254c7f558840b
pdf-font-stream PDF embedded font (sfnt) at offset 0xC729 16200 bytes
font_02_sfnt_off0000f08e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF08E 16792 bytes
font_03_sfnt_off000108a5.bin
49ee3249d00467b3c6e0bf012afa8a0a00bd03a39627941755a938cdde552d42
pdf-font-stream PDF embedded font (sfnt) at offset 0x108A5 10976 bytes