Malicious PDF — malware analysis report

Static analysis result for SHA-256 370dc8762f2e8d74…

MALICIOUS

PDF

69.9 KB Created: 2021-10-01 03:23:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 13b3c0bed92f8fe6e07dd369539dd822 SHA-1: 6cb7c8c41262744fceb2541268f176cdc34bfba6 SHA-256: 370dc8762f2e8d74b7c179e8f8521e51d5026813b6bd5a9c63087af4364e9391
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, with one heuristic identifying it as a link farm on disposable hosting. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest it is designed to redirect users to malicious sites, potentially for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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.
  • 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://wastran.ru/uplcv?utm_term=ppsspp+horror+games+for+android+free+download PDF link annotation
    • https://eguiders.com/uploads/gikeva.pdfIn PDF document text
    • http://otestmanager.org/club/data/userfiles/file/20210905105448.pdfIn PDF document text
    • https://fluffy-chins.com/images/file/14802876704.pdfIn PDF document text
    • http://orlickachata.cz/files/files/jeluvinilubiw.pdfIn PDF document text
    • http://dmychadla.eu/UserFiles/File/mofasu.pdfIn PDF document text
    • http://burmeseburmilla-allevamento.com/userfiles/files/16175543904.pdfIn PDF document text
    • http://aven.su/userfiles/file/25191083338.pdfIn PDF document text
    • https://mrdak.cc/uploadfile/files/nomekupik.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/8801534067.pdfIn PDF document text
    • https://aromamarketing.md/img/files/jotikalex.pdfIn PDF document text
    • http://dokturmice.com/ckfinder/userfiles/files/nutevex.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/28710154760.pdfIn PDF document text
    • http://abwmercury.com/uploads/files/kefijokaledovebo.pdfIn PDF document text
    • https://sanaspinler.net/calisma2/files/uploads/kisekoxuj.pdfIn PDF document text
    • https://curtain.jinware.com/upload/files/zawegijojavamurino.pdfIn PDF document text
    • https://yellowstonewildlife.com/7317046128.pdfIn PDF document text
    • http://www.psoevalledeabdalajis.es/ckfinder/userfiles/files/38431861918.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/dapoxufu.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/vq4vfftuhuc9cc4cr5olnvrs11/zavujuz.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/dosavumok.pdfIn PDF document text
    • https://harmony.im/userfiles/file/92050203161.pdfIn PDF document text
    • http://www.aragonemprendedor.com/userfiles/files/80378219624.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/11546085523.pdfIn PDF document text
    • http://tantusmarina.com/UserFiles/file/4999914936.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_off0000b16c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB16C 14804 bytes
SHA-256: c766cad401a811d3262f38e4f9a0a022ca04be40021b0e5e2b6069e90a6d9104
font_01_sfnt_off0000d6b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eec8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEC8 10936 bytes
SHA-256: d0f925016ae90d62b5ee6ef03145902e82f239c22454b8de4ac3c273b6785b7d