Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a7672e08d90e5b0…

MALICIOUS

PDF

70.7 KB Created: 2021-09-29 10:07:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 7e0d778cc1bea10462f5127fa349c81e SHA-1: 3c75f5ad12c2882c6ad7c8b527b834004c8ae249 SHA-256: 1a7672e08d90e5b0165cb2679eb59e0d29d38d1dcafaedf4e153bcc5203f9b4d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs pointing to various PDF files, coupled with heuristics indicating a link farm on disposable hosting, suggests a phishing or spam campaign. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://afayl.com/userfiles/file/68840870051.pdf In PDF document text
    • http://valencia.thepokeluau.com/uploads/files/96482201013.pdfIn PDF document text
    • http://snft.ro/media/file/zewibilaban.pdfIn PDF document text
    • https://gabinetpro.pl/kosmetyczka/krakow/files/xizitinaxizeniwefi.pdfIn PDF document text
    • https://miltonmattox.com/userfiles/file/2573904380.pdfIn PDF document text
    • https://panelshock.com/userfiles/file/34570816977.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/wapudisanoluve.pdfIn PDF document text
    • http://panyuchen.com/ckfinder/userfiles/site_eachfun_com/files/14836382367.pdfIn PDF document text
    • http://banhangcongnghe.com/upload/FCK/file/fevajabegusirogulise.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/50659515563.pdfIn PDF document text
    • http://makinsushi.com/uploads/files/xegabemajabenorola.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///pemufagerekisalibavizeso.pdfIn PDF document text
    • http://mlsy.cz/images/file/files/bavosuvusujukimu.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/891b80cc25f2eaf802b414acbfea2219/37281693053.pdfIn PDF document text
    • http://dienlanhhuubinh.com/upload/files/38937799119.pdfIn PDF document text
    • http://hbtsap.com/Upfiles/news/file///81689508383.pdfIn PDF document text
    • https://muguet.fr/sites/default/files/file/lesisalitafuzos.pdfIn PDF document text
    • http://tzoetemondje.be/uploads/files/11331656099.pdfIn PDF document text
    • http://xindeshiye.com/uploadfile/file///2021090612371266.pdfIn PDF document text
    • http://megalabsrl.it/userfiles/files/dupirepax.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/60028526614.pdfIn PDF document text
    • http://saigondome.com/uploads/userfiles/file/sabarixalefos.pdfIn PDF document text
    • http://sriagasthiyarastro.com/FCKeditor/userfiles/file/77686277229.pdfIn PDF document text
    • https://ivanamihic.com/files/23305604226.pdfIn PDF document text
    • http://mynotary.ca/sites/all/sites/mynotary.ca/files/9929743903.pdfIn PDF document text
    • https://www.dekleinewerf.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161410dc5be468---57752237838.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=pc+gta+codesPDF 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_off0000b1cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1CD 17828 bytes
SHA-256: d6920cdb4f3930515464d63723d08bd926d8a4b70b565e95d54b0efa26c95b68
font_01_sfnt_off0000de8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE8A 10204 bytes
SHA-256: 44b2778171c41f014bb35a9af100e60664bc72dbd56874c117f599ee39487ffd
font_02_sfnt_off0000f562.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF562 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1