Malicious PDF — malware analysis report

Static analysis result for SHA-256 d56981c9142bad4f…

MALICIOUS

PDF

79.9 KB Created: 2021-09-17 14:21:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 98bd97e26ed35ee3c0c3854740f3a56e SHA-1: f9d0ded11830fd144e7b08a162d9b107539326b1 SHA-256: d56981c9142bad4f35f46c5b26bf2b6441c10d1a50dcca020bbac4bcb85fa8f4
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable hosting and employing UTM parameters, suggesting a link farm or phishing lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high volume of links on potentially untrusted domains. While no scripts were explicitly extracted, the presence of multiple external URIs and the nature of the heuristics strongly suggest an intent to redirect users to malicious sites for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://pistant.ru/uplcv?utm_term=fundamentals+of+algorithmics+solutions+manual+pdf PDF link annotation
    • https://ketex.com/trcgp/ckfinder/userfiles/files/noromenatabafiguvob.pdfIn PDF document text
    • http://alfonsoguiggiarchitetto.it/userfiles/files/13618453312.pdfIn PDF document text
    • https://vetamblj.si/ckfinder/userfiles/files/towemefanefumege.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/dugilibaxenazisonagibinit.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/161421c8799fbd---6124070936.pdfIn PDF document text
    • https://hydratrend.com/application/third_party/ckfinder/userfiles/files/75595805455.pdfIn PDF document text
    • https://franciscovalles.comtraining.cl/userfiles/files/94971998981.pdfIn PDF document text
    • https://mkserwis.pl/userfiles/file/16702702170.pdfIn PDF document text
    • http://dreamsurgerycn.com/ckupload/files/85740150050.pdfIn PDF document text
    • http://ymjgolf.com/file_media/file_image/file/zepifasamekogukutemewo.pdfIn PDF document text
    • http://178.62.148.222:300/ckeditor/ckfinder/userfiles/files/zoguwafotegelezojebiz.pdfPDF link annotation
    • http://fujavietnam.com/images/Download/25900257492.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/kixuxegidibowinewafafiven.pdfIn PDF document text
    • https://hk-delight.com/UploadFiles/file/raxodojogekaduji.pdfIn PDF document text
    • https://bharatceramics.in/ckfinder/userfiles/files/xuxikuzorudalepir.pdfIn PDF document text
    • http://airmon.hu/images/files/wewoxugokedutumix.pdfIn PDF document text
    • http://lex.tj/img/file/kufolejasozarawof.pdfIn PDF document text
    • https://sts-cct.com/app/webroot/userfiles/files/kakixol.pdfIn PDF document text
    • http://pastadimatteo.com/ckfinder/userfiles/files/fasarubopapudix.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/gumedef.pdfIn PDF document text
    • https://bunexim.dascalita.ro/app/webroot/files/userfiles/files/xozapateganoni.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/6cf04754397e1325d4da2ec6bf8b1978/2467054041.pdfIn PDF document text
    • http://www.patriarca-batiment.com/ressource/site-image/files/lamonogilo.pdfIn PDF document text
    • http://alacarte-grafik.de/userfiles/file/milejurov.pdfIn PDF document text
    • http://apicn.net/upload/files/78109725471.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_off0000cfcc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFCC 18216 bytes
SHA-256: d68d0884cd31c80ce470c9e97f941c4703d375541b952fccd01ecf099d906358
font_01_sfnt_off0000ff8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF8F 11144 bytes
SHA-256: 4c4bb567f776f312ea6099ceb4fad9e1871b84d6710417bac67eb0cf9822303f
font_02_sfnt_off0001192c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1192C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1