Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cf16586706fa9cd…

MALICIOUS

PDF

82.9 KB Created: 2021-07-26 16:46:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3a2f65b5476c3c369243f4fb2c1e549a SHA-1: 636e00211a4aa2ad70332b5c1c9c8863739ffb7c SHA-256: 7cf16586706fa9cd416e1136c6610c3dbcdc95c513557461cce2e2689df105d7
156 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDF files hosted on various websites, many of which appear to be compromised. This behavior is indicative of a link farm designed to manipulate search engine rankings or distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b482fadcd97---foboregivegewikifopoxara.pdf
    • http://tks-forever.com/upload/2021/07/02/file/31998136170.pdf
    • https://pnp-studio.com/fckeditorfiles/file/88072059833.pdf
    • https://alves.bg/ckfinder/userfiles/files/77930123101.pdf
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/ca33dff1fb468e8aa86c14684436668e/5818441533.pdf
    • http://lube-stc.com/ckfinder/userfiles/files/54312700541.pdf
    • http://rund.cz/UserFiles/File/paxopejaguxezovapal.pdf
    • https://mldom.xyz/web/img/podborky/files/11453079115.pdf
    • http://npas.ru/pic/file/23377936431.pdf
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/d227d5e8243d789fce1584e6bbecd7b2/mugigajawa.pdf
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/7fceeu7ummuu0urbqrnj1lvbdl/wumugogikulesavip.pdf
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ab4837d2b2a---lemaduwivusekolibe.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a86f6eb84f2---padudixibimobej.pdf
    • http://www.idenet.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b9a388e9d---13155208778.pdf
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/o4idvb2hsutn31shl3adsn02d7/31392734141.pdf
    • https://sharpconsulting.us/app/webroot/ckfinder/userfiles/files/86672064309.pdf
    • http://crimesla.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fekavebelodorejek.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/160723d44908a6---xerilejokibes.pdf
    • http://wenxuezj.com/images/File/82954471424.pdf
    • https://triptoboloyfoundation.org/editorsfiles/files/2036197179.pdf
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160ee802e986f2---55063385424.pdf
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/4cda92e440841dae24b2a741ff3d6bd0/wibenejuwanuxusipuvej.pdf
    • http://apsencollege.org/test/fckeditor/file/fejaleluwubilevil.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=funciones+racionales+1+bachillerato
    • 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_off0000dcc8.bin
db782406c993e3462f5bb2606a5ac05cda19dca43aa0f8e020008983cd11d3e5
pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC8 17980 bytes
font_01_sfnt_off00010b57.bin
a78843be2d325c81d5bf9211c105fe8bac79ccb2ae6569145915dcbbe5cd23b1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B57 10596 bytes
font_02_sfnt_off00012386.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12386 16792 bytes