Malicious PDF — malware analysis report

Static analysis result for SHA-256 db8f7dbd5db8f1cc…

MALICIOUS

PDF

87.6 KB Created: 2021-09-18 06:47:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a4b81fbdf7160a45ca2a44771eccbc1d SHA-1: 4074a71e9343c51ffc016f5fbdcb54ec8fb515c7 SHA-256: db8f7dbd5db8f1cca915dcacc750a83fe54a540c6d0d62e368f3f418f1a176f6
196 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, pointing to multiple external URLs hosted on potentially compromised or disposable domains. The presence of 'LOLBin token sequence in document text' suggests an attempt to disguise malicious links or commands within the document's structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://keralastatetailorsassociation.com/userfiles/file/zuzerosol.pdf In PDF document text
    • https://ibericadearmerias.com/file/15362905126.pdfIn PDF document text
    • http://pjteam.hu/uploads/jotejomefuxijedirofu.pdfIn PDF document text
    • http://burchiellati.com/file_fck/file/vuvesofusemafimupub.pdfIn PDF document text
    • http://goldmustang.ru/files/files/34612767560.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210902220438.pdfIn PDF document text
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/2162477618.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/b610f2f74033f30c3034055a51711cf8/reviji.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/55415260040.pdfIn PDF document text
    • http://arndt-fahrschule.de/userfiles/file/dapoponunixilisij.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16141e2a464f90---23344718933.pdfIn PDF document text
    • http://charmingcurls.se/upload/file/5016729393.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141bc21dc57f---belopif.pdfIn PDF document text
    • http://pzhjintai.com/upload/files/8612827154.pdfIn macro / runtime command snippet
    • https://rent-1.es/ckfinder/userfiles/files/13139281399.pdfIn PDF document text
    • https://moderator.lt/components/com_mijoshop/opencart/image/data/files/zezusosezofojapozagaja.pdfIn PDF document text
    • https://gallerylingard.com/uploads/file/75340633133.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1613eafb05d0a7---selogovifalitilo.pdfIn PDF document text
    • https://careerroots.net/ckfinder/userfiles/files/82448843006.pdfIn PDF document text
    • http://bangtutrang.com/upload/files/70026288673.pdfIn PDF document text
    • http://gowowdeli.com/uploads/files/jesolixufekapizava.pdfIn PDF document text
    • https://martas.vodrsport.cz/uploads/files/72272738150.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/4ccca4c85afb099b2da3eb9e23cc7014/maxakedolut.pdfIn PDF document text
    • https://westhigienia.hu/editor_up/17585792399.pdfIn PDF document text
    • http://premiumresourcingIn macro / runtime command snippet
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=iphone+wont+message+androidPDF link annotation
    • 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_off0000f108.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF108 10828 bytes
SHA-256: 84746ccb1e2759f0aaef4eb7da235322ac0d4fbe3defdf7f37b2fc071042d745
font_01_sfnt_off000109a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109A8 18056 bytes
SHA-256: b3cf161009edd1400c5de978429693323a76e83e5bdc8cd67fb68db72d03f86b
font_02_sfnt_off000138a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1