Malicious PDF — malware analysis report

Static analysis result for SHA-256 5cef1311ffd18e5b…

MALICIOUS

PDF

85.4 KB Created: 2021-06-26 00:32:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cd553ef5dfb104994204ad7357619a36 SHA-1: 6f921c5ec2881b7557aa70c3de4751c64699245c SHA-256: 5cef1311ffd18e5b0c8835e79cc2f4b99a5dd49a770ffde9fbc4ef87926136cf
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the overall structure point towards a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff4edae9f0---vatisarakawu.pdf
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/v37f012u9gec6d29s5igp32bib/sudasexepatatuk.pdf
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e543335bb---fumowewewe.pdf
    • http://seoulsquare.com/userfiles/file/puwuwaned.pdf
    • http://peaceinsrilanka.lk/userfiles/file/zodokowawaxogevewumeruz.pdf
    • http://canvangdientu.com/images/file/91315649447.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b16fed12647---xugalemitimadegelonob.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a18893b1463---darozago.pdf
    • http://www.zywawiara.pl/pliki/sejekatutawav.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e2b431f1d---93782521926.pdf
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/lhcca29r7o8e1s9r6kshc09kv7/vimetewi.pdf
    • http://mvclassof1990.com/clients/8/8c/8ca0ba2c7a07c5cd1f21f9fc323c16c5/File/xujobumevif.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/2ccf924f9fc625a7fa358980f834ce73/4379161366.pdf
    • http://sibmetiz.ru/upload_picture/joxomegoxenotigumopoganu.pdf
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/c0107da1dc7a9b7b5de7adc186d23819/19307574795.pdf
    • https://aslimitada.com/userfiles/file/fafusorefagul.pdf
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a05ed67ef82---46032968586.pdf
    • https://questyme.com/userfiles/file/pasobugabikafo.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/ec4df65416e57d5c15e824cb9cdf6014/23849230023.pdf
    • http://deurenhanger.nl/userfiles/file/54290484368.pdf
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4e4dd7192a---74394039941.pdf
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddba62f572---79920606070.pdf
    • https://masterpieces-mallorca.com/wp-content/plugins/super-forms/uploads/php/files/12f6be3c45acc36a7cf4f59a084e5afb/maxufalofegizake.pdf
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/24om95qs9bted8cm00a51h88pq/gabopezutisogisi.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=resignation+letter+word+format+for+personal+reason
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9aa.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AA 16792 bytes
font_01_sfnt_off000101c1.bin
cac388c6b411d2a9f0153286cb193c1aa005155e853ce2950b13dbe875a004a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x101C1 10972 bytes
font_02_sfnt_off00011b0e.bin
018ddb2683b5519b2d0c1c21d1507896a34e57ff39276b812431c0a095753959
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B0E 17164 bytes