Malicious PDF — malware analysis report

Static analysis result for SHA-256 64bc7cb33f308e0c…

MALICIOUS

PDF

82.6 KB Created: 2021-09-14 01:36:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a127abe4cc3e38f072127a7a42ec8a66 SHA-1: 8696ea42f56ab0884b1b46ab82aedb0e6be6b10c SHA-256: 64bc7cb33f308e0c83d8374925b04057da6660bf05da9bb6e66d5a4e7b469687
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains. Several heuristics indicate this is a link farm, with some links pointing to compromised CMS upload storage. The ML classifier strongly flagged this PDF as malicious, suggesting it's part of a campaign to distribute malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 5

  • 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://expnavi.com/sites/all/sites/default/files/file/biwivisifoniputedam.pdf In PDF document text
    • http://mictrogiang.com/userfiles/files/lawop.pdfIn PDF document text
    • http://evpltravel.com/xv_image/file/gojapufefivabilaxomej.pdfIn PDF document text
    • https://www.renfrewareahealthvillage.ca/ckfinder/userfiles/files/88883940080.pdfIn PDF document text
    • http://indago-rovigo.it/userfiles/files/3846538051.pdfIn PDF document text
    • http://dharmapuridiocese.com/svnprojects/DHD/Source/images/files/84590128013.pdfIn PDF document text
    • https://360clothing.in/home/www360cl/public_html/uploads/images/files/xupexafulinikubogapuzek.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/20202354987.pdfIn PDF document text
    • http://bobiniauto.com/userfiles/file/diremiwapipavapopimes.pdfIn PDF document text
    • http://thegioituigiay.net/uploads/files/ziputikonofedizilu.pdfIn PDF document text
    • http://safeabortionnepal.com/userfiles/file/dezotiredevix.pdfIn PDF document text
    • http://mindennapi.hu/upload/file/67949534131.pdfIn PDF document text
    • http://goang-hann.com/uploads/files/202109071627598024.pdfIn PDF document text
    • https://aymexco.eu/ckfinder/userfiles/files/jevexufupibazidegutexolab.pdfIn PDF document text
    • http://se-ty.com/uploads/userfiles/file/molagef.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/40314795522.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210909014252731027l8bveho1tu0f.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/21db16c80d45d3cf3f19bc739ed38e45/jofixinisex.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613283ba40bd0---mozujukenisafaro.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/ff00e7b95fe880a6ff502a6182e4130e/91274877879.pdfIn PDF document text
    • https://anakmeong.com/contents/files/vesaso.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/fawaran.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=photo+hide+app+lock+downloadPDF 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_off0000dd86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD86 10524 bytes
SHA-256: f48088b00a983ee55fb1c03a32c286aab901d93cd4adf4453b2d9a5e7667791e
font_01_sfnt_off0000f57b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF57B 18308 bytes
SHA-256: 2bbe5308e172fc81005cc5fecef25e84d4571f5ff3a35a2d7f4d8dd040b26158
font_02_sfnt_off00012519.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12519 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1