Malicious PDF — malware analysis report

Static analysis result for SHA-256 20f1a8fafd21bf20…

MALICIOUS

PDF

75.4 KB Created: 2021-09-15 22:11:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 30ed1785611af48d8634d545a3f82f95 SHA-1: 386d02737278c605b6030733d4f8e845038d1256 SHA-256: 20f1a8fafd21bf20528a76fab94971cbbebdd59174c7a3b82c70b0fe7e58d94f
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple compromised or disposable hosting sites, including URLs containing 'utm_term' parameters suggesting phishing or SEO manipulation. The presence of numerous external URIs and a link farm structure points towards an attempt to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://synerhu.ru/uplcv?utm_term=dream+talk+recorder+apk PDF link annotation
    • https://jin-hung.com/userfiles/file/24110217546.pdfIn PDF document text
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613a407f9c57a---zugumenatakipemekuli.pdfIn PDF document text
    • https://hsse.hssanesteban.cl/files/gefimidetuguwokuwaresig.pdfIn PDF document text
    • https://dursunguney.com/userfiles/files/rubuselepowoxokase.pdfIn PDF document text
    • http://clinicaveterinariagussago.com/userfiles/files/velujadok.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613edecf8d1f9---99566311693.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/ukt8rmaa9gk0gt0sd8dbelher6/75666419398.pdfIn PDF document text
    • http://studiorumeo.it/userfiles/files/48964356795.pdfIn PDF document text
    • http://xn--80aaeiengkwpz6p.xn--p1ai/pub/file/tezijijadifegutaferewavu.pdfIn PDF document text
    • http://molenat-energies.fr/molenat.com/images/editor/file/sopili.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613d7e8ce698a---14633659078.pdfIn PDF document text
    • http://xn--22cjbbm2eyae3ehabdb4kqdtae3dxnnc1fhf.com/user_img/files/58228264587.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/disivekoled.pdfIn PDF document text
    • http://circolonauticofavignana.it/userfiles/files/femixuwujexanabi.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/tebimoxufemusamugova.pdfIn PDF document text
    • http://barahi.com/assets/userfiles/files/towikezukukevoridosimix.pdfIn PDF document text
    • https://festival.bg/fckeditorfiles/file/pulivozugowax.pdfIn PDF document text
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/f004a9ff852c31b90c44bfc254484489/rigegodirovojagateven.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/aps1iv5qc22thetm5cb966roso/luvisepat.pdfIn PDF document text
    • http://dworbieland.pl/userfiles/file/2719484246.pdfIn PDF document text
    • http://architettodrabeni.it/userfiles/files/zesameviwugeje.pdfIn PDF document text
    • https://netron.pt/app/webroot/media/files/22757545773.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133d5b52b37b---vusaxajidutufeva.pdfIn PDF document text
    • http://kfoodntea.com/dataroom/file/21784712469.pdfIn PDF document text
    • http://akvari-um.ru/userfiles/file/41809005682.pdfIn PDF document text
    • https://holycrosshealthcare.com/userfiles/files/22082516469.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_off0000c423.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC423 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dc3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC3A 10404 bytes
SHA-256: ea7076d614710e11978eb9305412f6b5fe78dd6a5e36486a458f5b0d5f909b8d
font_02_sfnt_off0000f3c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C9 17128 bytes
SHA-256: 396ce92b511a994dc9a0dbba109e85317dc5d43abaf6c034fb057d787cfdb365