Malicious PDF — malware analysis report

Static analysis result for SHA-256 c11c771f6102463a…

MALICIOUS

PDF

84.4 KB Created: 2021-09-18 13:06:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e6e8d468d8452e543abc18fb8f875ec5 SHA-1: a9a8c09d55c0c8d4d95827d8e988ec4f5f393b32 SHA-256: c11c771f6102463a50099d59601cc0cb62792175acb6994bb7945aad192bc861
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to direct users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://taaltoetsvo.nl/userfiles/file/72544326740.pdf In PDF document text
    • https://www.assofmt.org/ckfinder/userfiles/files/38390171452.pdfIn PDF document text
    • http://xycrusher.com/d/files/23355432562.pdfIn PDF document text
    • http://meditopthailand.com/file/wegizutewalixeroriwozede.pdfIn PDF document text
    • https://hlj-vibration.com/uploads/image/20210904/files/20210904101057.pdfIn PDF document text
    • http://cctsw.net/whly/up_files/FCK/file/20210905_235555_157.pdfIn PDF document text
    • http://cesarrodarte.com/userfiles/file/dorilijulapoligivofisotor.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/8127237257.pdfIn PDF document text
    • http://espacioschillout.es/images/admin/file/wolatawufasa.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/magupimaves.pdfIn PDF document text
    • https://ecohort.biz/userfiles/files/duxagibagigetidalijukag.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/88197337620.pdfIn PDF document text
    • http://way-of-spirit.ru/upload/file/42627922994.pdfIn PDF document text
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/76066377621.pdfIn PDF document text
    • https://speedwayinfo.hu/uploads/file/55078801391.pdfIn PDF document text
    • http://cukrarnakolbaba.eu/obrazky/files/gijunuwa.pdfIn PDF document text
    • http://ranjitabiswas.com/userfiles/files/15615501952.pdfIn PDF document text
    • http://zaragozalawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/56535310494.pdfIn PDF document text
    • https://designclarf.it/file/21101659769.pdfIn PDF document text
    • http://studiolegalebisantis.it/userfiles/files/kinosuw.pdfIn PDF document text
    • http://lokalsport.no/userfiles/file/todalaretesexifujonuxexu.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/fegevakuzel.pdfIn PDF document text
    • http://tuttotop.com/userfiles/files/13153545777.pdfIn PDF document text
    • http://morecoredesign.com/images/imageUps/files/titanoninukazazopewonipog.pdfIn PDF document text
    • http://iktoktatas.hu/files/file/xanikimisamawivuzosil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=add+exchange+calendar+to+google+calendar+androidPDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/kodod.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_off0000e12b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12B 19612 bytes
SHA-256: cdf2808a9ebdf1002b9b585a29cbfceecbd8c3fe7613327cd767c9ad3731db9a
font_01_sfnt_off0001131b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1131B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012b32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B32 10564 bytes
SHA-256: 91f41f636a6c3883f4abf53c83f7390542d7618a08c4e30b89a3e393cc9542ba