Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd79c5e69e0df5fe…

MALICIOUS

PDF

76.0 KB Created: 2021-09-12 07:06:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1f2dfc8545c43a7e6bf6d480e55f5451 SHA-1: 56d6a666431ff0075f6e4bbadaeb89ba5ba40c54 SHA-256: cd79c5e69e0df5fe9601475bf48f42f1b0a4f4d24f68187fd59e48b5cdf413d5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, embedding a large number of URLs, many of which point to disposable or unknown hosting. This suggests an attempt to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

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://optimumquestsolutions.com/ckfinder/userfiles/files/ruzowali.pdf In PDF document text
    • http://educasters.co/ckfinder/userfiles/files/zovosafa.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16132fbfb97117---bojexexawiniji.pdfIn PDF document text
    • http://baihsad.com/userfiles/files/20210909_160605.pdfIn PDF document text
    • https://getracemirates.com/userfiles/files/49183705778.pdfIn PDF document text
    • http://metafelix.it/userfiles/files/zalewese.pdfIn PDF document text
    • http://bakefruit.com/uploads/files/202109020837154750.pdfIn PDF document text
    • https://www.htlexpress.com/ckfinder/userfiles/files/misiwes.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/60559227833.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/98654868078.pdfIn PDF document text
    • https://betsin.org/userfiles/files/13017960664.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/files/21266589405.pdfIn PDF document text
    • https://primer-spb.ru/files/files/tibolebumalum.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/9729266846.pdfIn PDF document text
    • https://lecourbe.dk/userfiles/file/33625968690.pdfIn PDF document text
    • http://kmsenior.org/file/files/wedimi.pdfIn PDF document text
    • http://taociren.com/upload/file/210909130913024399wl9okpbk2k5d.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/161374950ced06---52495427122.pdfIn PDF document text
    • http://zl369.net/userfiles/file/wemiwugegapetikiluv.pdfIn PDF document text
    • https://kolbandibileklik.com/resimler/files/bufubevakenupakezazaridub.pdfIn PDF document text
    • http://sdds.be/userfiles/file/webifukuvexe.pdfIn PDF document text
    • https://oolong-dining-co.com/webroot/editor-uploads/files/lazurofitekatuve.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/55228782323.pdfIn PDF document text
    • https://szabolcsipeter.com/userfiles/file/lezagu.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/vezexidopegatuxe.pdfIn PDF document text
    • https://windsbs.biz/files/file/66263154911.pdfIn PDF document text
    • http://ancient-theater.gr/media/file/9509972250.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=how+to+get+rid+of+voicemail+notification+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_off0000c54e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC54E 16728 bytes
SHA-256: 0dc63e9e0e3c1d9aac5a168dc38e995814ad8ad1a2c29867e802d14808ab34fc
font_01_sfnt_off0000f091.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF091 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000108a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108A8 10796 bytes
SHA-256: b7f9c90329b8501a5d6ae146841e331d4c026879dc25bf9f27c220159005d9f3