Malicious PDF — malware analysis report

Static analysis result for SHA-256 43cf4fdc4c52e874…

MALICIOUS

PDF

86.6 KB Created: 2021-07-02 09:03:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0c7216974a9e3f5ce60bdafa3359c656 SHA-1: 43e092bfd9ecce882cdd6854883827c5c13900dd SHA-256: 43cf4fdc4c52e8741e1039ee9eba0b2626a5ef1739b699f6bd651c9a69931a44
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links, many pointing to compromised WordPress sites, suggesting it's designed to lead users to malicious content or phishing pages. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://chcial.ru/uplcv?utm_term=present+perfect+continuous+tense+function
    • https://eletvital.hu/uploads/files/50536987759.pdf
    • http://asfcursillo.com/clients/879797/File/duraxobukavezepalag.pdf
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/b46sav38k0guf5qvou2hf1l160/leteramapuwidebemitisan.pdf
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/f92ba97cf24bd9b021c8c56f0c3a676c/busulowipiselowe.pdf
    • http://cuanhomkinhtoanthang.com/media/file/43377376279.pdf
    • http://ipjanah.ir/wp-content/plugins/super-forms/uploads/php/files/mg6oqso3bv5cegv3m1qdvvt145/35905755505.pdf
    • http://trips-in.com/ckupload/files/dukulefodibipisa.pdf
    • https://soba05.org/wp-content/plugins/super-forms/uploads/php/files/b5530e49fd675ad8c33b15be8d0a2beb/44696431877.pdf
    • https://linhngapt.vn/upload/files/77254069902.pdf
    • https://www.duffylighting.com/wp-content/plugins/super-forms/uploads/php/files/8546feb9a084f527fc1963c79f63e4b9/32545618630.pdf
    • http://animalscipublisher.com/files/upfiles/file/mezivuzivopezadeturarini.pdf
    • http://ultraljud.nu/bild/files/vikonapisedifugoxef.pdf
    • http://sunarfactory.com/userfiles/files/femikapizarutelaken.pdf
    • http://thecreditcrisis.net/clients/73966/File/96403637640.pdf
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16070e15fe271b---vobukonikijaxerizudi.pdf
    • http://begemot-rus.com/uploadfiles/file/2021052218093973499.pdf
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/e8d2795cd45401f8ebfff29d6e02c87e/zepojidifumejaxagi.pdf
    • http://bainihu.com/upfiles/editor/files/81122892706.pdf
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/e783bbe7e62094954d2984cd63aebdba/75672704620.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/d3ec59d38bd254d444ab0e94fe20b6bb/jetaxovutakomazavikotovu.pdf
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac91d52ece6---wuwanutib.pdf
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c7332ca6f7---93019907932.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb9856a3a4---24101621554.pdf
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/1294f106f8dec19f8a4de5dc8661c87c/27693855454.pdf
    • 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_off0000ef45.bin
18551a3dc6c1c5b32f3f75a583d0d06b65729b9a90ffa90b3d794ae26d3c00eb
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF45 17052 bytes
font_01_sfnt_off00011b98.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B98 16792 bytes
font_02_sfnt_off000133af.bin
644aab22850a6beca07e816d30e4560813fceeb7d02c640b4b6f38e8698c9419
pdf-font-stream PDF embedded font (sfnt) at offset 0x133AF 10368 bytes