Malicious PDF — malware analysis report

Static analysis result for SHA-256 a80c52aa575d4d08…

MALICIOUS

PDF

78.7 KB Created: 2021-09-06 13:18:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 78246c2427fe4e10e50cb6d9e51b04b8 SHA-1: c9eb443bf2bd5df196a6c41af41a5e9e430c7de3 SHA-256: a80c52aa575d4d080ebd4eeced8e81ec4b55c0cb50f0b29d415646e4795e31dc
164 Risk Score

Malware Insights

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

This PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external PDF files hosted on various domains, many of which appear to be compromised WordPress sites or disposable hosting. The presence of a 'download button' heuristic further suggests a lure to download malicious content. The primary attack vector is likely spearphishing attachment, leading to exploitation for client execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3715ff3493---89988465052.pdf
    • http://www.miyadenthai.com/image/upload/File/36043276662.pdf
    • http://h-p-n.fr/catalogue_dynamique/file/detitufikiworunipa.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16115fdf9c2819---wosakoja.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612cec5d3eea4---49262630084.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081f973bc122---74676011651.pdf
    • https://useoneconvo.com/wp-content/plugins/super-forms/uploads/php/files/99d4ec0f6343537526e905c71937e0c6/67146887021.pdf
    • http://skybuildinfraprojects.com/uploads/wafur.pdf
    • https://2winit.com/Files/files/26229296298.pdf
    • http://tksvolga.ru/userfiles/file/99151524300.pdf
    • https://manajrgvaaradhi.com/cms-uploads/files/sudefoloporirokumerik.pdf
    • http://brezov-gaj.si/uporabnik/file/9351683737.pdf
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16097cdbfc6260---10259259128.pdf
    • https://anukulagrotech.com/ci/userfiles/files/putezujopi.pdf
    • http://slsnn.ru/content/file/xugejusa.pdf
    • https://sport-jicin.cz/dokumenty/lutidumaxixiwefazizu.pdf
    • http://weberstellen.ch/userfiles/file/73396314890.pdf
    • http://taiwan-tsai.com/upload/files/juxiposemex.pdf
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/svrcsnogafiu1s7jo002t94m9r/10787209509.pdf
    • http://divapharma.com/uploaded/file/satukebi.pdf
    • http://citescolairedeledit.com/include/file/1554311125.pdf
    • https://webhostmurah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611894829079e---kodotuloturofugatelor.pdf
    • https://francoisdaulte.com/ckfinder/userfiles/files/92872462011.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=manual+de+scanner+fujitsu+fi-6130+en+espa%C3%B1ol
    • 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_off0000c888.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC888 16792 bytes
font_01_sfnt_off0000e09a.bin
500cc91b6b0d3c9a4586153ee226650cbad1844d5a4fc5073eb4dd0fb1bf4ebb
pdf-font-stream PDF embedded font (sfnt) at offset 0xE09A 18072 bytes
font_02_sfnt_off00010f0d.bin
1cbf9a186862f71dcd83a566bc043f584fee6bea0296f65bfbb6e4dd7c18e046
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F0D 11592 bytes