Malicious PDF — malware analysis report

Static analysis result for SHA-256 0754aecb13abd0b3…

MALICIOUS

PDF

88.0 KB Created: 2021-07-09 16:22:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 16069056d77f0b9c8bb2736fd1017108 SHA-1: 75251830e6c534548ba45197b54c4104a3013263 SHA-256: 0754aecb13abd0b3a53a5eef14bd089ffc9b4d73fbdbd5fd9f90db092a105c70
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many of which point to URLs hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The document body is unreadable, but the heuristic firings strongly indicate a malicious intent related to URL redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • 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.
  • 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://valserve.in/web/k/main_admin/ckfinder/userfiles/files/nurugopofujekovofifipu.pdf In PDF document text
    • https://aduanaldelvalle.com/userfiles/file/98975556064.pdfIn PDF document text
    • https://boumqueur-edition.com/upload/fckeditor/file/bunuxidudivuvowogubunolej.pdfIn PDF document text
    • http://onnetsolution.in/userfiles/file/velaviretelolumivubojudu.pdfIn PDF document text
    • https://daleplumbinginc.com/wp-content/plugins/super-forms/uploads/php/files/02707a92a1359538959dc23370ab81ff/66003088105.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/47579474348.pdfIn PDF document text
    • http://mobiliteit.nu/files/fabaluzuwopu.pdfIn PDF document text
    • http://bogelaipigeon.com/upload/file/bikiduzalabolulo.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/dc5200f3a0c59822280ca207afd042f1/91025570895.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160795cde25c44---rirafebafunasorevovanamud.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a57f9a4f598---62653460670.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/dgr61vccgper9l81o4bnmajac3/99542117473.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c0acff9ac15---1937402591.pdfIn PDF document text
    • http://gtshotel.it/images/file/xepibenisad.pdfIn PDF document text
    • http://global-insurance-broker.de/downloads/tesukifobulezuguje.pdfIn PDF document text
    • https://salubrismd.com/wp-content/plugins/super-forms/uploads/php/files/502b6b9089619f0904705e3e203effc2/pamogusuwuji.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/xubesuvasofivetubapa.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607514d4a7b9f---bujamumevizanadopepazuj.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3a1e58a1ad---betodigomatijemelilaj.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/38999564450.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e282e9f252---73098353262.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799c1f7790e---32415686154.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210503020054_684807701.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=on+eagles+wings+funeral+songPDF link annotation
    • http://perfecturology.cafe24.com/upload/editor/imagefile/31701088748.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f5c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C8 10500 bytes
SHA-256: cd683dc8bf26b7ba027e315c3a476f2adaca30c35fb8a3e0c6d5528d6e3970e9
font_01_sfnt_off00010de4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000125f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125F6 17380 bytes
SHA-256: ed216884fa8d59c6c703ca4532a569862ae934a6c7db2768a8cc385888799ba2