Malicious PDF — malware analysis report

Static analysis result for SHA-256 55b729c6e151e0ee…

MALICIOUS

PDF

88.8 KB Created: 2021-09-18 22:07:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c2860b9538d266f31f99a336ab369a92 SHA-1: c22aa580a187b5d23e32b08293ca875eaf855701 SHA-256: 55b729c6e151e0ee8bb154845bc60631282d64a60d21c0a9d2c659bafbd50fcd
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with a high-confidence heuristic identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were directly extracted, the nature of the links suggests a potential for JavaScript execution or redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9764

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://allytemp.ru/uplcv?utm_term=torrentcounter+torrent+magnet PDF link annotation
    • https://ambulatorioveterinariosismondi.eu/file/puxowaxikubajadub.pdfIn PDF document text
    • http://infinity8talents.com/userfiles/file/wabozigus.pdfIn PDF document text
    • http://cserepakcio.hu/xdata/file/kuzanonoxepimegomi.pdfIn PDF document text
    • https://wedding-photos.cz/userfiles/file/71147490502.pdfIn PDF document text
    • https://mallncart.com/userfiles/files/89818016135.pdfIn PDF document text
    • https://almentispharma.com/ckfinder/userfiles/files/40865483882.pdfIn PDF document text
    • http://swotaweb.com/img/upload/file/47060648681.pdfIn PDF document text
    • https://auto826.com/uploads/files/tovabubetosiroparopob.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/45285582639.pdfIn PDF document text
    • http://cc-loges.com/uploads/file/gonewejerazuvovawofop.pdfIn PDF document text
    • http://www.pes.edu.mn/ckfinder/userfiles/files/69065399768.pdfIn PDF document text
    • http://ocean-ex.com/images/blog/file/dobodironezidisijetivuli.pdfIn PDF document text
    • https://indirimlipin.com/calisma2/files/uploads/zarudejokuzon.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/fapowikekenejagot.pdfIn PDF document text
    • https://asztromiskolc.hu/ckfinder/userfiles/files/reraleva.pdfIn PDF document text
    • http://nigerseedindia.com/uploads/1695008297.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9ea051376---vawemoli.pdfIn PDF document text
    • https://lbk-ingatlan.hu/uploads/file/fivuxulamusobaboroxutem.pdfIn PDF document text
    • http://etabetasurvey.com/userfiles/files/pazopifage.pdfIn PDF document text
    • http://nwatchonline.com/userfiles/file/bewepabuladawovagoviniri.pdfIn PDF document text
    • http://siamsnail.com/media/userfiles/files/25792491575.pdfIn PDF document text
    • http://zensushidanapoint.com/uploads/files/57842323425.pdfIn PDF document text
    • https://cebubigsellers.com/userfiles/file/70500441849.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/23342768818.pdfIn PDF document text
    • http://clubmaniacr.com/campannas/file/15561781309.pdfIn PDF document text
    • http://cluster006.ovh.net/~greeters/be/ckfinder/userfiles/files/zifasuwoberodez.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dcef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCEF 10328 bytes
SHA-256: a600c763ea27173ae2b94f749fc04c1eec1aba3fc6974966bc34acb2011f6092
font_01_sfnt_off0000f43d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF43D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C4F 17112 bytes
SHA-256: 4b64dbe750f6e7e1ccfb317c760789be6b9257d989f450361e38bf1d8b5a5c93
font_03_sfnt_off00013878.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13878 18264 bytes
SHA-256: 3df041d466e8a93a0776c5c3823e5fb905aa20e832c03504ab2e2e193ab0d045