Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1ef0c1c50f97713…

MALICIOUS

PDF

82.2 KB Created: 2021-09-17 12:15:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 567345241147780a28ea81a427f15caf SHA-1: 60b4d4deb3b9ae0f5326c051379a290d00bd0f97 SHA-256: b1ef0c1c50f97713f78c59c178dc9829ac4dcc1d493c47b935309b36fc309d89
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Heuristic analysis revealed it functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. These links, often containing terms like 'video downloader', are designed to lure users into downloading malicious content or falling victim to phishing attempts.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 6

  • 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.
  • 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://philabc.ru/uplcv?utm_term=video+downloader+free+download+apk PDF link annotation
    • https://thegioidongphuc.net/ckfinder/userfiles/files/47729544490.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file///mokepamolofar.pdfIn PDF document text
    • https://biserica-izvorul-tamaduirii.ro/files/98607205451.pdfIn PDF document text
    • https://claudiodituri.it/uploads/80504995787.pdfIn PDF document text
    • http://fresh-j.info/images/uploadedimages/file/46794427626.pdfIn PDF document text
    • https://cncunse.com/d/files/fawewelagosa.pdfIn PDF document text
    • http://weighlessthisyear.com/ckfinder/userfiles/files/roxusena.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/s8o6mqi15lmc2a9lttbovtaho4/batuwabaditi.pdfIn PDF document text
    • http://safetyassessmentsolutions.co.uk/ckfinder/userfiles/files/58728160.pdfIn PDF document text
    • http://virtuozi.ru/sites/all/sites/virtuozi.ru/files/87016822892.pdfIn PDF document text
    • http://firesecurity.sk/userfiles/file/terapekon.pdfIn PDF document text
    • http://sapientgenerator.ru/files/userfiles/files/78954082457.pdfIn PDF document text
    • http://graczeonline.pl/userfiles/file/lomizapubuvum.pdfIn PDF document text
    • http://webinaris.training/ckfinder/userfiles/publics/files/42575854371.pdfIn PDF document text
    • https://www.asoriofrio.org/ckfinder/userfiles/files/gebona.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612edfdc61255---nupedolovipugatodirifo.pdfIn PDF document text
    • https://garnizone.com/userfiles/file/bodinelu.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613ad64a5947a---jofen.pdfIn PDF document text
    • http://moscow-vernisage.com/files/files/58017421941.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/16130280ad27a9---59749344594.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/fifugunozixivelusemi.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/c75b05aa86768f95c9b1e13086412e4f/27601735641.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_off0000ddb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB0 10372 bytes
SHA-256: 42276ef99f2a16e4d790cec1cef6fa272b389d87cfe22ab5cac21d253cb9d68d
font_01_sfnt_off0000f538.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF538 17816 bytes
SHA-256: 9b934c3e5d8dec20a4f0467d4d8b4a899a4cf10c0065d4a70b7e8d10407e4e10
font_02_sfnt_off00012315.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12315 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1