Malicious PDF — malware analysis report

Static analysis result for SHA-256 98125a4def889719…

MALICIOUS

PDF

86.0 KB Created: 2021-09-10 12:53:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d474299dbb7051316e23ea5008134dcd SHA-1: 640f801340d2fcf59cb638825226913f8a6aceaa SHA-256: 98125a4def8897199186cb80a482d1536ecb345dd30e18d92bbc48a25cf05d57
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, including one identified as an algorithmically-generated URL hosted on potentially disposable infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for executing malicious code within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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 https://crewmak.ru/uplcv?utm_term=where+can+i+download+twilight+movies+for+free PDF link annotation
    • http://nhadatv.com/webroot/img/files/fonud.pdfIn PDF document text
    • https://bharatceramics.in/ckfinder/userfiles/files/runesudakaxoxisonaz.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/donuwedinimikenuw.pdfIn PDF document text
    • http://ilsogno-bomboniere.com/userfiles/files/dufogosusoboxetuzapuwabo.pdfIn PDF document text
    • http://vanillasky-ch.com/images/files/woxujotomilefozisefilis.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/zabunuzukigazitifo.pdfIn PDF document text
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/notum.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/69945148627.pdfIn PDF document text
    • http://virtualcharityevents.com/vce_cake/files/files/fijojagogim.pdfIn PDF document text
    • https://nomortiga.com/contents/files/13886367449.pdfIn PDF document text
    • http://ncdesign.it/userfiles/files/58217647623.pdfIn PDF document text
    • http://kustari.net/userfiles/file/37626393605.pdfIn PDF document text
    • http://kbautotech.com/board/datafiles/imagefile/gesuvuviragisimet.pdfIn PDF document text
    • http://www.predia.cz/userfiles/file/59643309341.pdfIn PDF document text
    • https://whereestar.com/marinarubicon/admin/file/54974602688.pdfIn PDF document text
    • http://ambulatorioveterinariopisillibertozzi.eu/userfiles/files/63236992917.pdfIn PDF document text
    • https://endeligmandag.no/e-brev/data/div/47475611049.pdfIn PDF document text
    • http://ecohouse-lab.com/userfiles/file/13149527826.pdfIn PDF document text
    • http://vinhthuan.com/upload/files/19215571691.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///15978923046.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613312c65da8b---pojufediwul.pdfIn PDF document text
    • http://scea.edu.mn/ckfinder/userfiles/files/demewilitojivelubo.pdfIn PDF document text
    • http://xn--o79av69abka850ab6c.com/upload/file/202109061757470379.pdfIn PDF document text
    • http://dreamwith.gni.kr/ckupload/files/59011914339.pdfIn PDF document text
    • http://ensky-chemical.com/upload/files/63120979667.pdfIn PDF document text
    • http://www.injamal.es/nueva/ckfinder/userfiles/files/48329458508.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_off0000ea48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA48 17764 bytes
SHA-256: 214ca7450b01abe6e6671b1541dc4d077402cda68b3d753feb2310951ce870cf
font_01_sfnt_off00011838.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11838 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001304f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1304F 11068 bytes
SHA-256: 79d7ba2d3a71f0d40f94061ec2600780cb94287b3032d3c0f40832e54077def9