Malicious PDF — malware analysis report

Static analysis result for SHA-256 28fc2c645bad3a6c…

MALICIOUS

PDF

86.3 KB Created: 2021-09-16 12:53:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 35c7e87d5aa3ee0d34103517c8040a15 SHA-1: 05e4e37654b8a21dfc946bced028874c91e1c6df SHA-256: 28fc2c645bad3a6ce1792cdc78b611ba475353a6a5daaa4bee8f222b40d0e2e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised WordPress sites and other disposable hosting, suggesting a phishing or malware distribution attempt. The presence of 'utm_term=download' in one URL indicates a lure to download software. ClamAV detection as 'Pdf.Phishing.Trojan' further supports a malicious classification. No scripts were extracted, but the structure and URLs strongly suggest a phishing or downloader attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://korsorlampang.net/user_img/files/mawuniwuvu.pdf In PDF document text
    • http://belovosushi.ru/files/17443079728.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/lajanebedokudido.pdfIn PDF document text
    • http://china-guolin.com/filespath/files/20210901231459.pdfIn PDF document text
    • https://balajitutorial.com/admin/userfiles/file/7479025727.pdfIn PDF document text
    • http://bitree.net/ckfinder/userfiles/files/vevojunavisaseda.pdfIn PDF document text
    • http://www.dawnrotaryclub.tw/UserFiles/files/vopufoxunugu.pdfIn PDF document text
    • http://rinsacars.com/files/others/17875176.pdfIn PDF document text
    • https://xtremefitksa.com/ckfinder/userfiles/files/40619827208.pdfIn PDF document text
    • http://alvitraders.com/files/30731445760.pdfIn PDF document text
    • https://dragonexpressml.com/userfiles/files/41131891076.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/pivonuzu.pdfIn PDF document text
    • http://changwontour.kr/FileData/ckfinder/files/20210910_F42A82164B2F8B5A.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/c36acbbc33d19ea4a9c8f19c5d8b31d3/35262147559.pdfIn PDF document text
    • http://aolisenjiancai.com/data/files/nadukekidofatadevazonofex.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/36c343b022e7ad42252a70979b9f92df/26127890174.pdfIn PDF document text
    • http://juncheng.tw/upload/files/famivomibufad.pdfIn PDF document text
    • http://www.bargiel.com.pl/ckfinder/userfiles/files/41993542597.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/deroridonugafowatumufoz.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141a686f256c---tapavubovomugugunujage.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/8337605478.pdfIn PDF document text
    • http://kpotplace.com/uploads/files/zizanegewirefuzusep.pdfIn PDF document text
    • http://basketaci.cz/UserFiles/File/lakonamuvigavifumovasoje.pdfIn PDF document text
    • http://thienlongadv.com/upload/files/4902670759.pdfIn PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/98084144287.pdfIn PDF document text
    • http://bresky.cz/res/file/31834577037.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=download+ppsspp+for+pcPDF 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_off0000ebca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBCA 10380 bytes
SHA-256: d975c9cd4999423a966135dfca4bc489d1690d42ffb2d1cb7943b1642a8c46be
font_01_sfnt_off00010371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10371 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011b83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B83 18344 bytes
SHA-256: 76f574f82c8f39d9d114247b5629ba958ab8f503d07b25f8f578e3678ebe97f7