Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1a8fdacf880839a…

MALICIOUS

PDF

85.0 KB Created: 2021-09-10 18:19:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 44726868ff411513aaf74605c86dbb31 SHA-1: 1a04b9d286cc10dc53432b344f36037b3d2d5f59 SHA-256: f1a8fdacf880839a8c7a1445d86c3fd74ba1806f2e9a22f66c3e1cb468e9a617
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ML classifiers and ClamAV, with critical and high severity heuristic firings. It contains embedded JavaScript, which is often used to download and execute additional payloads or redirect users to malicious sites. The PDF also exhibits characteristics of a link farm, with numerous external URIs pointing to potentially compromised or malicious domains, suggesting a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://omonetach.pl/foto/ilustracje/file/4047028764.pdf In PDF document text
    • https://ceccarmehedinti.ro/userfiles/file/putabipofukibibiv.pdfIn PDF document text
    • http://pibar.tw/uploads/files/202109050021525483.pdfIn PDF document text
    • http://thebrownbag.vn/upload/files/74327040215.pdfIn PDF document text
    • https://jairdefreitas.com/ckfinder/userfiles/files/68679561980.pdfIn PDF document text
    • http://andrelandberg.com/userfiles/file/51890857668.pdfIn PDF document text
    • http://sinching.com/uploadpic/files/202109091908212196.pdfIn PDF document text
    • https://softwebstar.com/shop/userfiles/file/44608431998.pdfIn PDF document text
    • https://saleskerala.com/ckfinder/userfiles/files/palute.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9a6a66222---vivubinupilakade.pdfIn PDF document text
    • https://www.adoz.cz/ckfinder/userfiles/files/fowuduwosisotajonim.pdfIn PDF document text
    • http://househouse.it/userfiles/files/3472373739.pdfIn PDF document text
    • https://ichapps.peaceofworld.com/ichapps/ckeditor-ckfinder-integration/uploads/files/94246528526.pdfIn PDF document text
    • https://guptajimarriagebureau.com/userfiles/file/57994058839.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/67353235477.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/reridumagaz.pdfIn PDF document text
    • https://cytairtool.com/test/userfiles/file/20210910_25f6d.pdfIn PDF document text
    • https://chokysitohang.com/Uploads/userfiles/files/95784705935.pdfIn PDF document text
    • http://curvesncontours.com/userfiles/file/wiwotejuriduw.pdfIn PDF document text
    • http://peach2560.xyz/js/ckfinder/userfiles/files/webebi.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16133c8ac6e6c1---tibolenedagunaboxedoru.pdfIn PDF document text
    • https://atrax.eu/userfiles/file/34332351236.pdfIn PDF document text
    • http://sakaryakasaplarodasi.org/userfiles/file/56076137956.pdfIn PDF document text
    • http://banglenhospital.com/UserFiles/File/sijibosikelodupu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=downloading+movies+on+android+tabletPDF link annotation
    • 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_off0000e65a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE65A 17932 bytes
SHA-256: 00f2155a40513d56850e6580ce11856e27356c284d3a7a73bbc39f503a67e7fe
font_01_sfnt_off000114c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012cda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CDA 10884 bytes
SHA-256: 3bf5d5b3b35681ae5699d8fcbb4cc191268f082aa8a161526c8b20bc58d8d1b2