Malicious PDF — malware analysis report

Static analysis result for SHA-256 aaf11259053df976…

MALICIOUS

PDF

85.3 KB Created: 2021-09-23 21:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 824a0ddbf7ab15f1d0e28dc8c7529636 SHA-1: a11746d7e990a6f2c7cddeb927338bc388c71a41 SHA-256: aaf11259053df976a1225a993ba04d8f8038805e8d467eeb82cadd9af6e3e185
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many URLs pointing to compromised CMS upload directories or disposable hosting. The embedded URLs suggest an attempt to lure users to external sites, likely for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 http://fundacjahfg.pl/upload/file/60010361285.pdf In PDF document text
    • http://gleb777.com/fck_upload/file/22511471457.pdfIn PDF document text
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/a007509f938f36a0b59caae905272e4a/7775256279.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/jexupifa.pdfIn PDF document text
    • https://albawadiroad.com/userfiles/files/bisipameburulolox.pdfIn PDF document text
    • http://bonezi.morefriendship.com/upload/files/16691163716.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/96198213418.pdfIn PDF document text
    • http://hzbmsj.com/images/upload/File/nutogu.pdfIn PDF document text
    • http://affordableadobe.com/ckfinder/userfiles/files/vegadujamavimikikaweva.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/161472983beed7---81436217023.pdfIn PDF document text
    • https://hkbca.org/UploadFiles/file/20210921203159194.pdfIn PDF document text
    • http://123dvere.sk/files/file/27564163639.pdfIn PDF document text
    • https://bhsbeacon.com/FCKeditor/file/41621646601.pdfIn PDF document text
    • http://www.advokat.com/app/webroot/img/fck/file/dalalazalu.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///sidepesitowisuxux.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614303e05f411---jekomelesewaperemi.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/9991a24f35c00a8e1902ab2b25e83c54/3328033476.pdfIn PDF document text
    • https://uslugiinzynierskie.eu/eurostyl/photos/file/10562732346.pdfIn PDF document text
    • http://mfahk.com/upload/files/11423819907.pdfIn PDF document text
    • http://mcap.cz/images/uploadedimages/file/vifejitazimoloxavoli.pdfIn PDF document text
    • http://isvpro.com/custom/files/39194172827.pdfIn PDF document text
    • https://defi128.com/userfiles/files/wofuvegekijikiwexebab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=horror+online+multiplayer+games+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_off0000e924.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE924 17584 bytes
SHA-256: b5e70f0aa334d15b774f16ac00c8d7a64e7a5165ec82fb343c46a974ee0e22ad
font_01_sfnt_off0001168d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1168D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012ea4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EA4 10940 bytes
SHA-256: 0e7bc629b6e1565ae96aee33ad46e9a8e2d2257f50187666e6a2791f7ac6ce25