Malicious PDF — malware analysis report

Static analysis result for SHA-256 da9513aa56feae8d…

MALICIOUS

PDF

76.9 KB Created: 2021-06-28 02:58:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: cc716a92b33ccc6a0067451bf00f0174 SHA-1: 5769cc4f65f2fe6bfa46bc7b82a1d4c27aee9a18 SHA-256: da9513aa56feae8d888e3f50807d2a907923831e070323dd6890190e8a0f70d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a link farm pointing to multiple compromised WordPress sites, suggesting it is used to distribute further malicious content or redirect users to phishing sites. No scripts were extracted, but the presence of numerous external links and the 'link farm' heuristic strongly suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc180224f1---74051735962.pdf In PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad4e4fe26ce---50959078334.pdfIn PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aec5b0d4546---wogonimuxazizikur.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a39c5596e7a---43179113116.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/fqndsoq907829oi5vrrnu29fr0/15620240954.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608237109fe92---rofed.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/gamivirexa.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084ef714cdb9---21190975427.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d90ca296dd---koxufo.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16079648d7f7d9---87514216648.pdfIn PDF document text
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160cc1906b38c4---42059243902.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///2021060412524_132569947.pdfIn PDF document text
    • https://minutesnap.com/wp-content/plugins/super-forms/uploads/php/files/636f5a82549f18ae7ff6961a73174303/91048335001.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/28209752396.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/zenufanorakuvege.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=nothing+but+the+truth+by+avi+summaryPDF 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_off0000ca1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA1A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e22c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE22C 16796 bytes
SHA-256: 6771de2c0997acb741b6cd033ee107b43e7864f8c882f4c88359293e3576a0a3
font_02_sfnt_off00010dd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DD0 10908 bytes
SHA-256: 3d15f2b16836dd4ad28e791f1358ae44c8487d47030209184db42de584a442f9