Malicious PDF — malware analysis report

Static analysis result for SHA-256 e0837a5e53158c83…

MALICIOUS

PDF

78.6 KB Created: 2021-07-20 23:31:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b39cff36c74a7dbf59aef491cd543380 SHA-1: 78b31ffed67c0f2dfd730d23a546cf78c8e67928 SHA-256: e0837a5e53158c8326db701514edd553173ca40d86ad45ca23cbd3ad8e2fe26e
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was flagged by a machine learning classifier and ClamAV as malicious, exhibiting characteristics of a phishing and trojan delivery mechanism. The document contains a link farm hosted on compromised WordPress sites, likely intended to trick users into downloading a password-protected archive, a common tactic to bypass gateway security. No scripts were extracted, but the presence of multiple URLs on compromised infrastructure strongly suggests a malicious intent to deliver a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160bf81493d457---2026363639.pdf
    • http://kingsfinancialconsulting.com/userfiles/file/tumatafa.pdf
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/89d9023dfb95c4242b8e1cd3940a3ab8/zumozutakolozag.pdf
    • http://www.corazondelsol.es/ckfinder/userfiles/files/dofeza.pdf
    • https://penzionradvanice.cz/res/file/tafixosoligetigosej.pdf
    • http://bfr-bialapodlaska.pl/userfiles/file/nebabidilezena.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/ba9d417c4add335d8bb5accf870def30/kuxulopufurus.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160d2f59478c7c---wezorabufaj.pdf
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606f553b10149---luzeja.pdf
    • https://zzhqhi.com/d/files/49445040068.pdf
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/6jttsi5ci4mg2cc116p2va9hgo/44539563779.pdf
    • http://impressivetravelvietnam.com/upload/files/59423833251.pdf
    • http://jan-fotografie.nl/upload/files/11890114145.pdf
    • http://deshdunya.com/blogimage/file/59978141726.pdf
    • https://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078fd8450f0e---57967069876.pdf
    • http://splogservice.ru/content/file/66253473452.pdf
    • http://villa-margherita.biz/userfiles/files/40947472781.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608136ec5ab4c---temolemuzakizutolipuze.pdf
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f15ae12e84---bovepuv.pdf
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a96c9428218---nitagelewofup.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/857af05608f15d4d53ddb2d1b069e773/19931108346.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/lnp2slq63ahuidf9jec9ne7a44/fonadofud.pdf
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/199791c290304ef6272a47322c184997/48000095650.pdf
    • http://www.empresasdelimpeza.info/wp-content/plugins/formcraft/file-upload/server/content/files/160875f31f04ab---74408476725.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=love+of+the+lord+never+ceases
    • 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_off0000d2a4.bin
baa46891ab00acc34c8c9ddc10282ca04eadf2290a988360d4e15ec89fcb5635
pdf-font-stream PDF embedded font (sfnt) at offset 0xD2A4 16388 bytes
font_01_sfnt_off0000fd16.bin
fe8549d60b4f00964aa15fb922109010acaebbe29d6fb552628e8f15a21c8e44
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD16 10504 bytes
font_02_sfnt_off000114f8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x114F8 16792 bytes