Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc7b9fa20c48c726…

MALICIOUS

PDF

69.9 KB Created: 2021-09-26 04:43:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 897af06ff60fa078550eb61861fe2ea2 SHA-1: 93a2fa489c9f081fff301532d98961c1b5a038b6 SHA-256: dc7b9fa20c48c72623279dcfb1ddb0351adcc8daa6760b9a4694c5bf209224b9
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to disposable domains, a common tactic for phishing and malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading further malicious content. No scripts were extracted, but the presence of external URIs and the link farm heuristic points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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=castle+td+download PDF link annotation
    • http://sunnyten.net/userData/board/file/75864681648.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131556236709---17790324391.pdfIn PDF document text
    • http://terfigyelokamera.info/files/file/wegesuledofajiruxovemaku.pdfIn PDF document text
    • https://chrmglobal.com/userfiles/file/dituradefuduloneke.pdfIn PDF document text
    • http://goldendoodlesofthesierranevadas.com/userfiles/file/wexamuwenixelawoxujadakop.pdfIn PDF document text
    • http://kvrhousing.com/uploads/bubegegipivujuligor.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614faec6914a2---malivemewe.pdfIn PDF document text
    • http://czpohledavky.cz/userfiles/files/firarupegerujajiburig.pdfIn PDF document text
    • http://zhxndl.com/uploadfiles/files/82758061693.pdfIn PDF document text
    • http://xn--80aagkbrca3apkgkee0a1bi.xn--p1ai/ckfinder/userfiles/files/leraka.pdfIn PDF document text
    • https://twinscooking.nl/twins/userfiles/file/83831831034.pdfIn PDF document text
    • http://kidneytracker.com/ckfinder/userfiles/files/jinifun.pdfIn PDF document text
    • http://metalzilembo.it/userfiles/files/jugumeguxejuto.pdfIn PDF document text
    • http://gidaero.com/upload/fckeditor/file/batifonezidokogowupagi.pdfIn PDF document text
    • https://matfplayer.com/calisma2/files/uploads/wogewuz.pdfIn PDF document text
    • https://ideylia.fr/uploads/file/21233257998.pdfIn PDF document text
    • https://serka.com/serka/upload/files/53681756507.pdfIn PDF document text
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/66202964782.pdfIn PDF document text
    • https://emartdeko.pl/galeria/file/jederobodobenek.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/fevufupixuwivo.pdfIn PDF document text
    • http://mamnonhieutrung.edu.vn/ckfinder/userfiles/files/sulopolekaduvovupuwivaro.pdfIn PDF document text
    • http://chafewyuok.handysociality.com/upload/files/98206393919.pdfIn PDF document text
    • https://dlt-nkp.com/fileupload/file/77776359149.pdfIn PDF document text
    • http://caratow.nl/userfiles/file/wepolin.pdfIn PDF document text
    • http://xn--o79av69abka850ab6c.com/upload/file/202109021324361020.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_off0000b12b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB12B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC942 10168 bytes
SHA-256: 51c5809cdc48d7afa88ab3f99388eb822a2279b4e2c2f048d219f7e81f7231b9
font_02_sfnt_off0000e03a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE03A 16816 bytes
SHA-256: 15b201fcefc196f8c54ee328cc0d62a7a2e3788c414bb3cf779f7edfb527a6e0