Malicious PDF — malware analysis report

Static analysis result for SHA-256 b901fa9577461ef9…

MALICIOUS

PDF

73.8 KB Created: 2021-09-20 09:47:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d13eed0812dc33e5c740fae109db1ab9 SHA-1: 80a9cfc4758e9ca7e44a27c307902c1887837eac SHA-256: b901fa9577461ef9d717d65181da784010070441599f7ea35a0d168de6f6a038
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and multiple external URIs, including a link farm heuristic indicating a high volume of links to disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to exploit vulnerabilities or redirect users to phishing/malware sites. The embedded JavaScript is likely used to facilitate the download or execution of a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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
  • 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.
  • 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=fundamentals+of+biochemistry+pdf+free+download PDF link annotation
    • http://dsraxys.com/uploads/wuzarovodoni.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/20324330191.pdfIn PDF document text
    • http://ivelinabozilova.com/userfiles/file/11795397766.pdfIn PDF document text
    • http://bearings-home.com/userfiles/file/50797228261.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/gidisedasinuxefirokovup.pdfIn PDF document text
    • http://biafrapol.pl/pliki/file/bufunenadakedabiw.pdfIn PDF document text
    • https://felixtrail.com/imagini_ws/50164085824.pdfIn PDF document text
    • https://strongpointmarketing.net/userfiles/file/58280097949.pdfIn PDF document text
    • http://jinruily.com/UploadFile/file/20210918080104692.pdfIn PDF document text
    • http://thegioimercedes.com/upload/files/51992146207.pdfIn PDF document text
    • http://park-seversk.ru/other/js/ckfinder/userfiles/files/nerulidarafumu.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/ximejote.pdfIn PDF document text
    • http://etkenkalip.com/files/11321725351.pdfIn PDF document text
    • http://sushiyaslo.com/uploads/files/bekajevojegasefopuxon.pdfIn PDF document text
    • http://hla.vn/upload/files/48684696230.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/161339b7bbdd94---50866569312.pdfIn PDF document text
    • http://thaisomboonautopart.com/userfiles/files/26732466221.pdfIn PDF document text
    • http://soupworld.de/upload/file/39779599994.pdfIn PDF document text
    • https://gedayapi.com/userfiles/file/27660515091.pdfIn PDF document text
    • http://davidhammerstein.org/userfiles/file/84786560798.pdfIn PDF document text
    • http://shipagents.nl/uploadfiles/file/81957057665.pdfIn PDF document text
    • http://pallenberg-busreisen.de/uploads/files/powumokovewoxugenumewo.pdfIn PDF document text
    • https://hunde-katzen.at/soubory/25706854018.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c20f5c5dc6---dofuxuvaf.pdfIn PDF document text
    • http://paintmaster.hu/js/ckfinder/userfiles/files/pezagixedemanojudokugoson.pdfIn PDF document text
    • https://taptigrihnirman.com/singhania/downloads/file/jorasuf.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_off0000bd06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD06 11304 bytes
SHA-256: e463089d15155ab56111dd40e6ea54d8703485b037ba1f99ee88419159b10592
font_01_sfnt_off0000d739.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD739 16248 bytes
SHA-256: e1746512cd42e03f6e46eb2a9a4b97c54828345e1d3f19a143fc8ae8ec3a8d60
font_02_sfnt_off0001009f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1009F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1