Malicious PDF — malware analysis report

Static analysis result for SHA-256 09983873d9b865c2…

MALICIOUS

PDF

83.2 KB Created: 2021-09-20 01:14:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d23dd8a41c1b3dd35ebc403202164459 SHA-1: 9d312e0188581b1182c728f6012e012b4c2f914e SHA-256: 09983873d9b865c253e994296f4caf607a1440c25a0471fa18accd76ca938930
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The embedded URLs and the overall structure suggest an attempt to distribute malware or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://bepcongnghiepphuchung.vn/userfiles/file/pawama.pdf
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210916174530.pdf
    • http://toroisg.com/public/images/files/majodexazux.pdf
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613669168a885---zemijavabegisapomefuvu.pdf
    • http://jmk.kr/ckfinder/userfiles/files/kanomi.pdf
    • http://parikshitconstruction.com/uploads/sawavogufit.pdf
    • http://es-iyashinomori.net/yamituki-n/uploads/files/28205288857.pdf
    • http://hcm-invoice.vn/hinhanh_fckeditor/file/56172245495.pdf
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/j3g65u2gmr7tf7s3nhmfhs3q3s/majudarenitupof.pdf
    • https://ita.kru.ac.th/ckfinder/userfiles/files/91005446043.pdf
    • http://actlogistic.vn/upload/editor/files/55990229651.pdf
    • https://schreinerheusi.de/wp-content/plugins/formcraft/file-upload/server/content/files/161328a40366c4---sudalik.pdf
    • https://yingzhaoliuart.com/upload/file/90391193729.pdf
    • http://tantusmarina.com/UserFiles/file/24831558491.pdf
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/45b57ad6a8bc8248a77853c65cc29339/31674752284.pdf
    • http://creatinglifeoptions.com/userfiles/files/42362003984.pdf
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613abf4a3dbbf---10714660998.pdf
    • http://jezirka-biobazeny.cz/UserFiles/File/14885105166.pdf
    • http://agriturismolataggiasca.eu/userfiles/files/josetadorofuwipesunisuxim.pdf
    • http://madiagranitosilano.it/userfiles/files/wokoredikiwoxujogara.pdf
    • https://apgr.eu/UserFiles/file/dudalutakuted.pdf
    • https://seeyounow.net/userfiles/file/vuparozaxuzevoru.pdf
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145654755fc5---96077804516.pdf
    • https://majubesar.net/contents/files/newilusufej.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=a+noun+that+starts+with+x
    • 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_off0000df1f.bin
cea72eebcb7938b4bcf04456cc08617a9d9fac0bce1a166abbf9d65dca6bcd4c
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF1F 10296 bytes
font_01_sfnt_off0000f65b.bin
1a554677550cab36213037cdab62cddd6b085944d4e7e8f41069e92afc0dfad7
pdf-font-stream PDF embedded font (sfnt) at offset 0xF65B 18900 bytes
font_02_sfnt_off0001275e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1275E 16792 bytes