Malicious PDF — malware analysis report

Static analysis result for SHA-256 3a793ab5fd58c628…

MALICIOUS

PDF

85.7 KB Created: 2021-07-03 08:41:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e97d3d577fc51ba5dbfb4d702a81c108 SHA-1: 26154e45ee6d01ce762a40a381a048cbd62963e4 SHA-256: 3a793ab5fd58c628a4420022c7d2cf9a67dd839a88e1148ca0409a503d441c38
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic firings suggest the PDF acts as a link farm, potentially luring users to download further malicious content disguised as invoices or payment requests. Multiple URLs hosted on compromised CMS platforms and disposable hosting were extracted, increasing the risk of the user being directed to a malicious site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://pistant.ru/uplcv?utm_term=food+expenses+in+accounting
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a65983b4d71---36361527795.pdf
    • http://pro-group.ru/userfiles/files/popivevotiwaseridemibemam.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c66bf63a1f0---51578826924.pdf
    • https://callhfelectric.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a573166eb8---gatazopipepojasare.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/xatuvowodiloxejisegozilo.pdf
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/90mcaqfurs0bghhletmcoe8g67/63155069598.pdf
    • http://highendschmiede.de/highendfiles/file/47013997432.pdf
    • https://hasekei.jp/userfiles/file/jivoluxos.pdf
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/0e290ac4f990188400ebc9a34917515f/87895548592.pdf
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/bd94bc9df1d56d999927fff81e52f82a/40800595942.pdf
    • http://pumarecovery.com/userfiles/files/25731528801.pdf
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/56e4045305fe0e2ae7e858e5401d7e0f/lirexizixotobelusozuv.pdf
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160af82b173f54---59802280687.pdf
    • https://abe-rdc.com/userfiles/file/2426440558.pdf
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160aebcd563cf3---6950506714.pdf
    • http://noahsmarinesurveyors.ca/userfiles/file/mizebifenowod.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099a110cdd0e---81484162376.pdf
    • http://asckhn.com/acskhn/userfiles/file/lufejexovid.pdf
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/pncdcab2lofk9lqg9op6gitil1/86634996006.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/eec50b23b6690da40af3d5d1a1d80aa9/zajugavufavubok.pdf
    • http://nedirajtebosnu.net/userfiles/file/wezekagazifosesebi.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1609aea4371fdd---xadoguxe.pdf
    • https://marljivo.hr/userfiles/file/89564782245.pdf
    • https://epiphanych.com/images/file/wiwuzakag.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_off0000ea1c.bin
a3e79598e9c7a228e2a04973f7721eb6e26233b21bd54a7405bbbb89c947b513
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA1C 17292 bytes
font_01_sfnt_off00011738.bin
2063133490f510f114a0f1f53910bb3582e2790abd3bcaa26864363df5c6b7d1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11738 10724 bytes
font_02_sfnt_off00012fd3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12FD3 16792 bytes