Malicious PDF — malware analysis report

Static analysis result for SHA-256 991736f7f60358ee…

MALICIOUS

PDF

81.6 KB Created: 2021-09-17 09:42:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: a42207ff685820ae872653bed8198c3b SHA-1: 61fba8ba1f06e739c06ece51359e639d79c97ef6 SHA-256: 991736f7f60358ee59a706d1e070b581b1d8f01c1e9e6796e48e76cfdfb46162
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs pointing to various domains, suggesting an attempt to redirect users to potentially malicious websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for multiple links, further supporting a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://philabc.ru/uplcv?utm_term=videoder+app+download+new+version PDF link annotation
    • http://yourtruck.be/upload/ckeditor/file/getezonobukokurubomi.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/685ses9t1an1re9pilrjfjqul1/borotobuwibezikonofulolo.pdfIn PDF document text
    • https://kapokcmassage.com/uploads/files/202109061611303303.pdfIn PDF document text
    • http://autoneza.cz/UserFiles/File/wejiwewilazivetew.pdfIn PDF document text
    • https://willes-gb.com/uploads/files/202109071238223063.pdfIn PDF document text
    • https://univerosg.com/ckfinder/userfiles/files/34891856433.pdfIn PDF document text
    • http://jakpaisanestate.com/images/upload/files/gijomegewod.pdfIn PDF document text
    • http://uniquecharacters.com/upload/files/50323569998.pdfIn PDF document text
    • https://kmkmekanik.com/upload/ckfinder/files/bogigajonolagoju.pdfIn PDF document text
    • http://namuvaldymas.lt/userfiles/file/mizaka.pdfIn PDF document text
    • http://terminsk.by/pics/files/70006153022.pdfIn PDF document text
    • https://cheesykeju.com/contents/files/26882383629.pdfIn PDF document text
    • http://lishasurgical.in/ckeditor/ckfinder/userfiles/files/bexezosudiwaguwubilun.pdfIn PDF document text
    • http://worshipedia.net/sites/default/files/file/48894222071.pdfIn PDF document text
    • http://3gr-group-com.gbintl.com/ci/userfiles/files/gotebomisefo.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613ecec06a649---zaguvemukizopuwiwax.pdfIn PDF document text
    • http://thuduchouse.vn/pics/file/vixuvakoxolivef.pdfIn PDF document text
    • https://sakura-bashi.com/uploads/files/202109071901112575.pdfIn PDF document text
    • https://komunalno-vrgorac.hr/files/vulizenasetupebevusev.pdfIn PDF document text
    • http://md-servicios.com/userfiles/file/46611434906.pdfIn PDF document text
    • http://ptk-tent.ru/userfiles/file/39875536269.pdfIn PDF document text
    • http://atreve.eu/ubezpiecz/obrazy/file/goxuvutowetej.pdfIn PDF document text
    • http://trungtamsangloc.vn/uploads/ck_upload/files/86942579155.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_off0000db03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f315.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF315 18080 bytes
SHA-256: 639b94972bd4a791c8f017aa3903bbf2589af6117ca0126d3124a805697eabac
font_02_sfnt_off00012187.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12187 10408 bytes
SHA-256: 1b3d8eea5172d6736876c666409335a29ad88be61b882d31a328db8215fa8e76