Malicious PDF — malware analysis report

Static analysis result for SHA-256 4998c4932e622d6b…

MALICIOUS

PDF

79.4 KB Created: 2021-09-18 01:14:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d0d008938859b515af5c385be0bb7d70 SHA-1: 6c70c77726c778f8e2f89f36b35c6f0200d317c6 SHA-256: 4998c4932e622d6b3f8517b6ef6ddacf5dc2ef6414ff7340d3005088aaa3eeca
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many of which point to other PDF files hosted on disposable domains, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading a secondary payload or visiting a phishing site. The presence of embedded JavaScript (T1059.007) further supports the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://crysiq.ru/uplcv?utm_term=android+os+iso+for+virtualbox PDF link annotation
    • http://tochuchoinghi.org/files/66519580490.pdfIn PDF document text
    • https://sbmhavacilik.com/userfiles/file/xufote.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/34904123915.pdfIn PDF document text
    • http://www.madiran-cruduparadis.fr/ckfinder/userfiles/files/lazekufasovezenusefonene.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d08fa0ffcc---zigigujofibigubiz.pdfIn PDF document text
    • http://riverside-plaza.com/upload/userfile/files/nanodiga.pdfIn PDF document text
    • http://work4shop.cz/userfiles/file/xenozumiruwa.pdfIn PDF document text
    • https://ceccargiurgiu.ro/userfiles/file/88009205532.pdfIn PDF document text
    • http://topspeed4wd.com/ckfinder/userfiles/files/narelorutiz.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///14621077552.pdfIn PDF document text
    • http://xsteelstock.com/d/files/68335375991.pdfIn PDF document text
    • https://cartolmania.it/file/51728995744.pdfIn PDF document text
    • http://smsgurugram.com/miet/assets/files/tetewanogalaninaziw.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/161379950d65ce---mikezusose.pdfIn PDF document text
    • https://transturist.ba/ckeditor/ckfinder/files/files/77129604990.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/52849097241.pdfIn PDF document text
    • http://karthikeyanjayaram.in/userfiles/file/zuxakiniwiwalanaxu.pdfIn PDF document text
    • https://lawtutors.co.uk/js/ckfinder/userfiles/files/83456204470.pdfIn PDF document text
    • https://abhrian.com/userfiles/files/19678858678.pdfIn PDF document text
    • http://17njl.com/userfiles/files/vasufeb.pdfIn PDF document text
    • http://eros-arena-reutlingen.de/eros/userfiles/file/33767050159.pdfIn PDF document text
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/mixoz.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_off0000d2d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eae8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE8 17560 bytes
SHA-256: 8e93a23a392a9fcedfd74e33425623b8000065b6b50977b5b349c1a5185f5032
font_02_sfnt_off00011820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11820 10604 bytes
SHA-256: 40145cc9357a1eb4e6d80251fba00075ccf356ac114c62217ca00dba89aff881