Malicious PDF — malware analysis report

Static analysis result for SHA-256 2308a2e96a37631c…

MALICIOUS

PDF

87.7 KB Created: 2021-09-16 03:37:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 579ca048985d7d090f3701b72b530443 SHA-1: f675bc35ad9ce3c8533b6913f4f525cb283bc1a3 SHA-256: 2308a2e96a37631c26a4b0a683a2618fdc6d899bc96ea5a4bd94a280a53097c9
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. The PDF also features a link farm pointing to multiple distinct hosts, several of which appear to be compromised WordPress sites, suggesting an attempt to distribute further malicious content or phish users. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://art-lan.ru/uploads/assets/file/vugorelumonoke.pdf
    • https://horgaszvelem.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/penuzozumaj.pdf
    • http://parateam.cz/file/54994150512.pdf
    • http://curvesncontours.com/userfiles/file/turimufituwedawi.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613711be0b55d---89294703116.pdf
    • http://www.beautyvogue.ch/Files/file/voxibexazol.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f9ad053f43---64707278247.pdf
    • https://bloc-immo.com/images/26101289408.pdf
    • http://longbienco.com/js/ckfinder/userfiles/files/6129522598.pdf
    • http://yourhandmadeitems.com/userfiles/file/76581415995.pdf
    • http://kibunajcc.com/ckfinder/userfiles/files/bitudosup.pdf
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613a15b42f632---68046460073.pdf
    • http://lukoilmarine.com/ckfinder/userfiles/files/94012925919.pdf
    • http://pass38.com/images/contentimages/files/ridixudofogolaxa.pdf
    • http://papierplus.pl/userfiles/file/43855379166.pdf
    • https://songhongresort.com/img/files/78781164797.pdf
    • https://e-fasteners.eu/media/file/54334343645.pdf
    • https://annekienlen.fr/imagesfile/47428371850.pdf
    • http://snft.ro/media/file/venafajuji.pdf
    • http://sjzhtchem.com/upload/files/wefilukakogomemamujazo.pdf
    • http://edu-family72.ru/content/images/uploads/file/25009262701.pdf
    • http://redeyeldn.com/userfiles/file/68265248523.pdf
    • http://simsvizag.com/contentimages/file/11533052542.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=hp+snapdragon+835+termurah+2020
    • 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_off0000ee5a.bin
02c94c549d7fc27cc258fb1f55511074fb0037e6247e7764d06e1e44c8c07058
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE5A 11548 bytes
font_01_sfnt_off00010961.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10961 16792 bytes
font_02_sfnt_off00012173.bin
fe923a6f87183eafc9c93835b33082ff387af3efff4996e2231dc160826c5c3d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12173 18424 bytes