Malicious PDF — malware analysis report

Static analysis result for SHA-256 4017f51c294bcb85…

MALICIOUS

PDF

100.0 KB Created: 2021-08-08 23:03:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a5a9f7a9504bdcf645572bd81947c23 SHA-1: 1ff5f4827bdfed36b19379f2ed72d87368e84071 SHA-256: 4017f51c294bcb853ad89c20769810b35eec2dd90363f2725c0febd04bf597c5
196 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious. It contains a heuristic indicating a 'Clipboard command execution lure,' suggesting the document instructs users to copy and paste commands into a shell. This is a common technique to download and execute secondary payloads from external URLs, such as those found hosted on compromised CMS upload storage.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • 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://poornasreehomeoclinic.com/ckfinder/userfiles/files/vozeziloziratel.pdf
    • http://duszek-lasu.pl/userfiles/file/femobixefuwafaput.pdf
    • http://prime-standard.com/piceditor/file/tojidusof.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/g5p3c51iktslakpkjspt46ghh9/zabadadunumofekosogajuvu.pdf
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/160c6762a1189d---borevigodisaweg.pdf
    • http://sostrevalli.it/userfiles/files/134427244.pdf
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1ab376269---pubuwimilozisinujopivosox.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/bea8dc5743c1ed67df2d10aea57bc7f9/fajagutaxagepesekapod.pdf
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/2df615939e6c30e94e9e7206c4db8b14/53265996306.pdf
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/317b639bdbaa024c452e504acf3f8247/60988015351.pdf
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/48272433978.pdf
    • https://ssvacancy.com/ckfinder/userfiles/files/20529169022.pdf
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/1881ffc39bdfbbbdcd987248f578c413/xazorimexato.pdf
    • https://o2opr.co/userfiles/files/wuvoxuxek.pdf
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160aa256a079c1---7532838414.pdf
    • https://aawyx.com/sites/default/imageuser/file/dewilavofej.pdf
    • http://esistore.com/userfiles/file/23395494025.pdf
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0cb5819cd2---momajuluravap.pdf
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160d4017e19f74---pumipofelukowonisumubo.pdf
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a879fb30291---40601427716.pdf
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160836bbc44a83---49506107271.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=windows+10+pro+activator+txt+msguides
    • 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_off00011b31.bin
013180b227e1389dc4754efb74e9c3966de1c68da2d7d4b37fcaf2ac7ffe212d
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B31 18724 bytes
font_01_sfnt_off00014d1e.bin
b06f93bfcc1deb063e2a5c8016b31c7c22793577d7d448d0f95e9d2a379020ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x14D1E 11332 bytes
font_02_sfnt_off000167b2.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x167B2 16792 bytes