Malicious PDF — malware analysis report

Static analysis result for SHA-256 21c0889b733c435d…

MALICIOUS

PDF

88.1 KB Created: 2021-09-12 20:13:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 30ab78a8c30511842a0df498d3c922af SHA-1: da970ab5f121295bce0c22d01428412c52768ba4 SHA-256: 21c0889b733c435db53dd742e90e427e4b75323a31caff70759745a5254d9757
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a remote-support lure. It contains numerous links to external sites, many of which are hosted on compromised or disposable domains, suggesting an attempt to redirect users to malicious content or phishing pages. The presence of embedded JavaScript, though obfuscated, indicates potential for further malicious actions like downloading additional payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://medvor.ru/uplcv?utm_term=screenconnect+android+client
    • http://www.gpkoaee.ru/ckfinder/userfiles/files/pojibetewisovokutam.pdf
    • http://erpsamik.com/ckfinder/userfiles/files/91819980285.pdf
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/1a2e08003845c400a8653b76ae9d5eb7/59519673340.pdf
    • http://managhantasala.net/mailuserfiles/file/42749328939.pdf
    • http://wolfpackbasketballacademy.com/content_docs/51873275849.pdf
    • http://fszhenjia.com/upfolder/e/files/20210908114656.pdf
    • http://mtkshop.com/images/uploads/file/xeguxubak.pdf
    • http://northcity.rs/slike/files/8410317348.pdf
    • http://rideco.hu/upload/file/sifejajodafuximun.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613782903ac94---373393375.pdf
    • http://sterenstein.ru/userfiles/file/24163607144.pdf
    • https://heritagecambodiatravel.com/userfiles/file/zoxudipijikezuwabu.pdf
    • https://lacgl.org/upload/editor/file/jezirusamunaga.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d61345b76f---tikagubavobidigelej.pdf
    • http://sushiosushi.com/uploads/files/34601219034.pdf
    • http://mtjjt.com/2013/upload/article/files/210909150456627049gy9mn.pdf
    • https://tessuno.com/upload/files/6132389dcbe02.pdf
    • https://excellencetogether.com/img/files/file/rumedare.pdf
    • https://inprovitbrasil.com/ckfinder/userfiles/files/xoxevozo.pdf
    • http://dogomanhnghia.com/uploads/files/regemelobutero.pdf
    • http://indianapit.thriftstorewebsites.net/flash/indianapit.thriftstorewebsites.net/file/zelizekanuzelok.pdf
    • https://wrd13.com/force/file/55882147781.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_off0000f10e.bin
363e0738f6495070c4e8914198532c9fc83469c436de0a8aa556bcf5797de3b7
pdf-font-stream PDF embedded font (sfnt) at offset 0xF10E 10268 bytes
font_01_sfnt_off00010842.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10842 16792 bytes
font_02_sfnt_off00012054.bin
a9cc7d3ead38d0ed2baeb9548cdd8092a70d0113abb37c8b9afd5c788ce0df5d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12054 19272 bytes