Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5091644a011e033…

MALICIOUS

PDF

96.0 KB Created: 2021-09-10 19:51:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8dd7055916713c20afceebf7d864426c SHA-1: 9c0c53a1d9aee0aa166e975e1f4003b9666e5ade SHA-256: e5091644a011e033a65e331c1cc81a64577d580049526d4bbc26aecfae92ee4b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The PDF contains numerous embedded URLs, many pointing to distinct hosts, consistent with a link farm. One URL, http://phupmirpol.pl/userfiles/file/48186038227.pdf, is identified as a potential entry point to this farm. The document body is heavily obfuscated, preventing analysis of its direct content, but the overall structure and heuristic firings suggest a phishing or SEO manipulation scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://phupmirpol.pl/userfiles/file/48186038227.pdf In PDF document text
    • http://anoh.net/pds/userfiles/files/841584630.pdfIn PDF document text
    • https://herfection.herfection.tw/upload/ckfinder_temp/files/20210910104946.pdfIn PDF document text
    • https://12tiga.com/contents/files/zewerimabitisimuba.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/60293943701.pdfIn PDF document text
    • http://iact2001.com/userData/board/file/30912990401.pdfIn PDF document text
    • https://keluargamimpi2.com/contents/files/muzunoduzozisobuni.pdfIn PDF document text
    • http://cp-tournament.org/ckfinder/userfiles/files/pizuvojataxewadoluzil.pdfIn PDF document text
    • http://homeopathyhongkong.cn/files/degiru.pdfIn PDF document text
    • https://foundationkuzmanov.com/files/18286743990.pdfIn PDF document text
    • http://hzxgdz.com/images/upload/File/fumamu.pdfIn PDF document text
    • http://jiuxingchaoshi.com/uploads/file/101357336554.pdfIn PDF document text
    • https://renesens21.com/ressources/upload/files/71354738464.pdfIn PDF document text
    • http://mayepnuocmia.vn/data/ckfinder/files/26931475678.pdfIn PDF document text
    • https://kingcom.edesign.fr/gr33/web/uploads/assets/file/sanedazowama.pdfIn PDF document text
    • https://vocembalo.ch/userfiles/file/19651813482.pdfIn PDF document text
    • http://innovad-ltd.com/userfiles/file/lipetilul.pdfIn PDF document text
    • http://goldcoil.com/uploadfiles/files/galovuriwijanono.pdfIn PDF document text
    • https://sportsslife.net/upload/ckfinder/files/nujorid.pdfIn PDF document text
    • http://chafewyuok.handysociality.com/upload/files/dedifis.pdfIn PDF document text
    • http://improntediteatro.it/userfiles/files/tevufuj.pdfIn PDF document text
    • http://www.ecrivains-consult.fr/easyonline/ckfinder/userfiles/files/zivujaxitabinawugo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f1d95a7cde---41344699210.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/ea1603814139a6c4c52761c94bc60826/19514185552.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/lumotaxelami.pdfIn PDF document text
    • https://olboihorgaszto.hu/editor_up2/revukufavadufugonibo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=opengl+on+androidPDF 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_off000113a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012bc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BC0 10324 bytes
SHA-256: 59a62d53867c1e4a167db1370c435d3af750ef48041903c7b80f232a7cde7e51
font_02_sfnt_off000142dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142DC 17952 bytes
SHA-256: 0f77c0a0b677e5ae543270f2b87c6629a1a71da85dc1f547d52a24f3e9a79a1f