Malicious PDF — malware analysis report

Static analysis result for SHA-256 2dc4083d3825436c…

MALICIOUS

PDF

84.6 KB Created: 2021-09-17 10:27:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 3b05a2351b4a36cfc22d5f510f5bf839 SHA-1: 683d6c026b3c928b13b099cf2d5ef2206e9ab658 SHA-256: 2dc4083d3825436c909249d3d83c4fdfa6798523c2c68428c2b3f4dc50e691b8
146 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URIs, some pointing to raw IP addresses, suggesting a phishing or redirection scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports this, indicating the PDF is designed to host many links on disposable domains. While no scripts were explicitly extracted, the nature of the embedded links and the ML detection point towards a phishing attack that likely exploits PDF vulnerabilities or redirects users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://nomylo.ru/uplcv?utm_term=super+mario+bros+browser+emulator PDF link annotation
    • http://www.herbertvanderbrugghen.nl/draft/40626802502.pdfIn PDF document text
    • http://dnestrovsk.es-pmr.com/constructor/dnestrovsk/ckfinder/userfiles/files/56063390544.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/vebivexi.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/19515139821.pdfIn PDF document text
    • https://lotte-ppta.net/beta/assets/file/wikufefanidigodifezetefo.pdfIn PDF document text
    • http://seyrimerdin.com/userfiles/file/81751437035.pdfIn PDF document text
    • http://change4best.ru/upload/file/sawimigefudijev.pdfIn PDF document text
    • http://destockbaby.com/ckfinder/userfiles/files/xivalazoturuli.pdfIn PDF document text
    • https://etravelbox.com/scgtest/team-explore/uploads/files/xifumu.pdfIn PDF document text
    • http://vangphutai.com/images/uploads/files/fefuva.pdfIn PDF document text
    • http://kdwatch.net/upload/files/2021090111140728.pdfIn PDF document text
    • http://www.farmaciabergua.com/userfiles/files/visibebire.pdfIn PDF document text
    • http://redskap.ru/userfiles/file/53182653617.pdfIn PDF document text
    • http://qlionshousing.ca/userfiles/file/letavolikeva.pdfIn PDF document text
    • https://likeevent.it/writable/public/userfiles/file/47705989266.pdfIn PDF document text
    • https://twr1115.net/files/fckeditor/file/76316200873.pdfIn PDF document text
    • http://betonkeritesek.eu/Content/files/kuguzuxuxepalurevijoga.pdfIn PDF document text
    • http://fra2ange.it/userfiles/files/gezixabexoke.pdfIn PDF document text
    • http://140.121.125.49/ckfinder/userfiles/files/20210903_030706.pdfPDF link annotation
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137d29897270---gerumidixagavekizoka.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/af7rhcp06o608vbmn3cnvlehb7/55924700068.pdfIn PDF document text
    • http://farmaciafasolis.eu/userfiles/files/pazugezemaxifapewedal.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_off0000e448.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE448 18740 bytes
SHA-256: e631ce0cbd9f96ee532104d9715fc96cb320e8951f7f5b09f273d1f9f40c378f
font_01_sfnt_off000114e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114E6 10712 bytes
SHA-256: 05822ded32c441e5b890eab065eb29aa192aec5d82d2d002d7b06a4ad167aff2
font_02_sfnt_off00012d58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1