Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd2b1272e5e193f4…

MALICIOUS

PDF

86.7 KB Created: 2021-09-22 11:20:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 491d3b9a828f0d62f8736ab9f60f4b08 SHA-1: 39c2284a57bb6b0a86e7963bb2003649e69627f2 SHA-256: fd2b1272e5e193f47e036c0f454232165ff885d485b9adcb5304aa70d8253a58
204 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple external URIs, some of which are hosted on compromised CMS platforms and are part of a link farm designed to improve search engine rankings. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a phishing or trojan payload. The heuristic 'SE_LOLBIN_RUN_COMMAND' suggests an attempt to execute commands, possibly via PowerShell, further supporting a malicious execution chain.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://smidgel.ru/uplcv?utm_term=lightroom+app+download+for+pc+windows+7
    • http://sualpturizm.com/userfiles/file/pusopowexunigovalipoza.pdf
    • http://udelimpa.es/ckfinder/userfiles/files/15184978398.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161390ae4591ef---51701853067.pdf
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/19895796124.pdf
    • http://studioguagnoni.it/userfiles/files/dojusiwapunowevebulemer.pdf
    • http://tentimesneedlehill.com/UPFILE/userfiles/files/lotas.pdf
    • http://viprealestatebrokers.com/userfiles/files/94272326672.pdf
    • http://xinghui.co/upload/ckimg/files/202109090431543541.pdf
    • http://beachfirebrands.com/userfiles/file/lutozogomo.pdf
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/80ca1e4a5aa01966891f11e2be0eec15/letememudupeme.pdf
    • http://uniquecharacters.com/upload/files/84499279628.pdf
    • https://pannonfinanz.eu/editor_up/sumatanava.pdf
    • http://tea-ra.com/user_data/upload/save_image/files/66682754786.pdf
    • http://skisun.it/userfiles/files/61736531674.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614644df6b2d0---ginijefuneledugaza.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/161431fce6582a---8546187374.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16136ec0dd5782---zesomorejaje.pdf
    • http://packamate.com/userfiles/95989853414.pdf
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/nugixotogozalojuwekam.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_off0000e9b3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B3 16792 bytes
font_01_sfnt_off000101c5.bin
b874c260a28ef0e4ae5b8f810f699e97eaced2f082aaf35a3734be5684b46591
pdf-font-stream PDF embedded font (sfnt) at offset 0x101C5 19292 bytes
font_02_sfnt_off000133fc.bin
984de5b4299fd9589e5bdb21bef1f5f366dc3fd8a80606a70f9136d0bbe31918
pdf-font-stream PDF embedded font (sfnt) at offset 0x133FC 11028 bytes