Malicious PDF — malware analysis report

Static analysis result for SHA-256 590061b02dbe0488…

MALICIOUS

PDF

69.2 KB Created: 2021-09-12 08:04:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2a9714518fa18d403945b2938d274968 SHA-1: 6625a6977cb4a2ad5482e85dd49935acf9587553 SHA-256: 590061b02dbe04889cdc45a9709aaaa45ab052115adeacd3e126bb0a843d9cdd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was identified as malicious by ClamAV and an ML classifier. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised CMS upload directories or disposable hosting. The presence of 'utm_term' parameters in some URLs suggests a phishing or SEO manipulation attempt. No scripts were extracted, and the document body was unreadable binary data.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://shinies.ru/img/lib/file/61541759099.pdf
    • https://triptoboloyfoundation.org/editorsfiles/files/segokaruleg.pdf
    • https://atiksigorta.com/files/95070484504.pdf
    • https://anne-berger.de/sites/anne-berger.de/files/fkcfile/93275650745.pdf
    • https://gamma-electronics-eg.com/userfiles/files/roduvebod.pdf
    • http://sangjeom.com/userfiles/file///28120621569.pdf
    • http://classicalgardenornaments.com/uplds/file/77813253091.pdf
    • http://ageofwonders.buka.ru/sadm_files/madegisafemewewerasif.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/161342bd309bc7---52851888907.pdf
    • http://www.feniuniversity.edu.bd/app/webroot/ckfinder/userfiles/files/90269857004.pdf
    • http://wwpokebar.com/uploads/files/67564566117.pdf
    • http://tjsyjdq.com/v15/Upload/file/20219522504840.pdf
    • http://gameometria.com/assets/ckfinder/core/connector/php/uploads/files/91557981415.pdf
    • http://sosonomo.com/ckfinder/userfiles/files/79168239278.pdf
    • http://cokhitienvuong.com/uploads/files/10165279633.pdf
    • https://signatureshreyas.in/userfiles/file/97988676256.pdf
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/e858d9252457036ec204364c3a5492c2/kumiguzuvujazugakulerakat.pdf
    • https://gregoryshow.ru/files/file/wudoresezugopibanokurig.pdf
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/e14c0951000e0ed59111a7375be219af/82911738111.pdf
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb0e6331c1---27785147466.pdf
    • http://michalpavlicek.com/uploaded/file/xebukusexa.pdf
    • https://laser123.com/geektic/files/bamavugepevixugenu.pdf
    • http://wyadonline.com/userfiles/file/34851552035.pdf
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/8d3f88292a7d7199f2e832f87c58550b/49975116826.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=sbk+mobile+game
    • 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_off0000b2db.bin
3921246903a711d51fe9e364b7b11a3c4b7365b82196023a01a292031fa91cac
pdf-font-stream PDF embedded font (sfnt) at offset 0xB2DB 14884 bytes
font_01_sfnt_off0000d834.bin
5301449eb3721fbd9d27cd8543ea41723f02679c11194000ded06eefad08032a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD834 10288 bytes
font_02_sfnt_off0000ef61.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF61 16792 bytes