Malicious PDF — malware analysis report

Static analysis result for SHA-256 afc17749d6470f70…

MALICIOUS

PDF

76.5 KB Created: 2021-09-10 01:28:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: bb54beedd60f1142126a49f21d5b2155 SHA-1: dde8c2582e3167dad1f510528b5e2aa74ad10b28 SHA-256: afc17749d6470f70750c5b830ad20c32f4914f73617bb85896dbe6a853b490bf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm pointing to compromised CMS uploads and disposable hosting. The PDF contains numerous external URIs, suggesting an attempt to redirect users to potentially malicious websites. No scripts were extracted, but the overall structure and URL patterns are consistent with phishing or malware distribution lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://wastran.ru/uplcv?utm_term=miui+12+for+redmi+note+8 PDF link annotation
    • http://malifer.hu/upload/file/luvuwi.pdfIn PDF document text
    • https://rajnnuhiddje.se/userfiles/file/pepifotosefufarof.pdfIn PDF document text
    • http://cualuoiskydoor.com/webroot/img/files/xosipotebakebolubuxufesa.pdfIn PDF document text
    • http://xn--9w3b270a7kf.kr/ckfinder/userfiles/files/51089583635.pdfIn PDF document text
    • http://dungcumaymoc.com/Images_upload/files/zidopizax.pdfIn PDF document text
    • http://axi-hohenstein.de/userfiles/file/bitudo.pdfIn PDF document text
    • http://nhasachconggiao.com/luutru/files/44260043556.pdfIn PDF document text
    • http://www.ez4parcel.net/upfile/files/2021/09/01/31638238776.pdfIn PDF document text
    • http://eszixv.hu/ckfinder/userfiles/files/mafesisotawuloketu.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e6cedb60f---sewunigasajomi.pdfIn PDF document text
    • http://ticketsperiodico.com/galeria/files/16465528387.pdfIn PDF document text
    • http://spbmedaks.ru/sites/default/files/uploads/dawufora.pdfIn PDF document text
    • https://oasis-travel.ro/files/37275214747.pdfIn PDF document text
    • http://ozt.zielonetarasy-cieplice.pl/uploads/userfiles/files/51979034512.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/25442315611.pdfIn PDF document text
    • https://togelunited4d.com/contents/files/rerunu.pdfIn PDF document text
    • https://aksusu.com/upload/files/fudirilelagigavilip.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/timaf.pdfIn PDF document text
    • http://xn--krmer-dnnebacke-1kb72b.de/files/file/toguvi.pdfIn PDF document text
    • http://aiaato.com/FileData/ckfinder/files/20210906_F7A041FED45EA188.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/ppfra2aimpqmfb21r4m3sg4buq/bakel.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613658ab6a330---77410006556.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB623 21564 bytes
SHA-256: 9a75442fb4e95477f2d22e79d97f6556416fc6cf3a8829f5b6dd0c2fa7debd79
font_01_sfnt_off0000ec26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC26 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010433.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10433 1680 bytes
SHA-256: 6c08887b596ecb472c5a0482df8c2f828d83fc5b5d16111ed0caa1fced1b35dc
font_03_sfnt_off00010c30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C30 10612 bytes
SHA-256: 5a270baa0c045322c6776131026c00630508b274700e8c1de83d320cd4ff0fd3