Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff45035bcd412770…

MALICIOUS

PDF

84.0 KB Created: 2021-09-19 02:14:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ef6667676b2980b7b3c0674c91a8ae39 SHA-1: ac256e9c05c5394d909d876b34f00df2d2d989b0 SHA-256: ff45035bcd4127705146d63c7cd9c189fc13f6945e3a9e8a1fd921b582c4804d
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URIs, suggesting it is designed to redirect users to potentially harmful websites. The malformed stream length heuristic also points to exploit activity within the PDF structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://huntic.ru/uplcv?utm_term=area+of+parallelogram+and+trapezium+worksheet+pdf PDF link annotation
    • http://adance0112.com/upfile/editor/file/vodugikul.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/99a35a6577075558d1c413f3111a5648/98466330950.pdfIn PDF document text
    • http://taikenplan.jp/ckfinder/userfiles/files/68572725152.pdfIn PDF document text
    • http://rund-sro.cz/UserFiles/File/bewugetosatebareroxijum.pdfIn PDF document text
    • http://onsijsselstein.nl/userfiles/files/67548158175.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/defb4740852810bf632800f91778b443/bisizagarijugajetamun.pdfIn PDF document text
    • https://dbmotorbrokers.com/userfiles/file/zimoraterajopa.pdfIn PDF document text
    • http://getampedmag.com/ckfinder/userfiles/files/fixebunudifulepobomabi.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/10155494292.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/nedujukewolejut.pdfIn PDF document text
    • http://digifast.cz/userfiles/87462561758.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/91337931153.pdfIn PDF document text
    • http://klinok-saintp.ru/files/tudufanerodun.pdfIn PDF document text
    • http://dbcasagayathottam.org/assets/uploads/cms_images/files/zunuzokoket.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/11186834988.pdfIn PDF document text
    • http://myappartement.de/web/editor/files/34000146684.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202109021954214848.pdfIn PDF document text
    • https://spvi.cn/filespath/files/20210902130757.pdfIn PDF document text
    • http://wo-kop.pl/userfiles/file/81587740304.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/54643989461.pdfIn PDF document text
    • http://furniture83.com/upload/files/xejivuwep.pdfIn PDF document text
    • http://bioscipublisher.com/files/upfiles/file/zumipex.pdfIn PDF document text
    • http://advertisingreports.info/assets/ckfinder/core/connector/php/uploads/files/64528935270.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_off0000e2b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fac2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAC2 17732 bytes
SHA-256: 5a25902954c6d37041529e6292fca06dbf472fddc52adcd7ccdff2cc9be1fcec
font_02_sfnt_off000127c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127C3 11264 bytes
SHA-256: df2c0dfb84e935d90a0d73fcce8109a8acd2eb597c18ba5c7a48f7273bcf45a1