Malicious PDF — malware analysis report

Static analysis result for SHA-256 51a94064870bceb3…

MALICIOUS

PDF

75.0 KB Created: 2021-09-16 21:01:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d18dc9523f74f343dbf1fd6a75ab5d95 SHA-1: 733929e22b0698e30a3c487548079cc1d6b0e867 SHA-256: 51a94064870bceb3db03ea629075680caf59170fbdd4ca032ea04fafe1e7a70e
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, including one identified as an algorithmically-generated URL. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of JavaScript suggests an attempt to execute malicious code or redirect the user to a compromised site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://irlanc.ru/uplcv?utm_term=how+to+get+free+v+bucks+in+fortnite+season+5 PDF link annotation
    • http://tjsyjdq.com/v15/Upload/file/20219162246367007.pdfIn PDF document text
    • http://dulwichtaxi.com/survey/userfiles/files/44247379474.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/zuvame.pdfIn PDF document text
    • http://salukool.ee/upload/userfiles/file/1285029693.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/80565030569.pdfIn PDF document text
    • https://frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/bukiwumemisati.pdfIn PDF document text
    • http://ambulatorioveterinarioilghirlandaio.it/userfiles/files/zefixaduxoroxegopape.pdfIn PDF document text
    • https://bisnismedsos.com/userfiles/file/56064060697.pdfIn PDF document text
    • http://pascalparrot.com/uploads/assets/file/wisilulerapuwivebagara.pdfIn PDF document text
    • http://kino-cosmik.ru/sadm_files/sagegomoruzobazuz.pdfIn PDF document text
    • https://sakkestadbil.no/userfiles/file/61447459289.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/vixedi.pdfIn PDF document text
    • https://afritransport.com/app/webroot/files/file/86018443456.pdfIn PDF document text
    • http://dichvutheapec.com/upload/FCK/file/38908473055.pdfIn PDF document text
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/4877058440.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/161376b6446556---8214168883.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/19787117273.pdfIn PDF document text
    • http://escrima-rlp.de/userfiles/file/dixegamufoz.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/sikesojafisapofuveposuku.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109042227147155.pdfIn PDF document text
    • https://www.newhorizonscrisiscenter.org/ckfinder/userfiles/files/waputaw.pdfIn PDF document text
    • https://sahyadrisevasanstha.in/userfiles/file/5971610084.pdfIn PDF document text
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/sokebifuguvoromugemaxaba.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/6f7m8h5752dro4j8ojfs7q4704/digitav.pdfIn PDF document text
    • http://gs-metals.com/filespath/files/20210902142313.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_off0000c186.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC186 11076 bytes
SHA-256: 89807271d4a8c37ad6520503c18814d01c7d646f44668f71cf5c802e96ffa6fa
font_01_sfnt_off0000db97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f3a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A9 16592 bytes
SHA-256: cc595402ba0da4b74c2af12b7b24febbea264eae32a700a865c72df7e41a9dd7