Malicious PDF — malware analysis report

Static analysis result for SHA-256 1443eebcc893ec56…

MALICIOUS

PDF

122.2 KB Created: 2021-08-14 11:44:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e78a7e7a27a2ff8a83ea4f9a184c8d24 SHA-1: 166c68eac176ced730fa8e2f583d6d1ed2c6d597 SHA-256: 1443eebcc893ec563d6167eb9d56bcaa3306dcfa0a499ee6c969a08567d5ead9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting a link farm used for redirection. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with phishing or malware delivery campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://crysiq.ru/uplcv?utm_term=building+macromolecules+worksheet+answer+key
    • https://catequesisnavarra.org/guiarte_userfiles/files/kipimupozowosekisud.pdf
    • http://aksaaydinlatma.com/img/editor/image/file/77749614172.pdf
    • https://baatco.com/ckfinder/userfiles/files/patijudobivewe.pdf
    • http://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a68c620091---8247167202.pdf
    • http://ezibra.pl/upload//file/sabosan.pdf
    • http://teplospectr.ru/images/files/futimobaluxurixipuzo.pdf
    • http://barcelonasixtytwo.com/userfiles/file/78833864627.pdf
    • http://czdashan.cn/uploadfile/file/2021050523140673499.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/f671b3e1c8b657afc797dc999591971a/88241448429.pdf
    • https://arnetbilgisayar.com/upload/ckfinder/files/37841619091.pdf
    • http://hbleg.com/admin/userfiles/files/fijup.pdf
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/4a27a5252c65a25a4fb588dfd44ba0aa/38324427929.pdf
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa383ae08a1---39638233365.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/9c926677f2a4b21033a2427b7c684239/14445461746.pdf
    • http://karthikeyanjayaram.com/userfiles/file/mesanewasofukifi.pdf
    • https://shieldtech.cz/ckfinder/userfiles/files/veloxoku.pdf
    • http://illinoislivestock.org/userfiles/file/29086575349.pdf
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/bf7cb92aa6b1f5111f5da18c72916237/kugewarijugejus.pdf
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/27d6b93ab477225a70000ae3c3c89a62/viwerumozabujeguz.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/jdmfm6716348hau5g24ed6a355/4506263422.pdf
    • http://hhs63.org/clients/8/88/88ec95b665b56da82b1de85f097fba10/File/4468709154.pdf
    • https://allmassage.net/upload/file/20210513085929.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_off00017766.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17766 16792 bytes
font_01_sfnt_off00018f7d.bin
4f00dedb9edcadd0f76fa24efe2fb39b5e1309e1fa1143db6bb72c9053e17133
pdf-font-stream PDF embedded font (sfnt) at offset 0x18F7D 11260 bytes
font_02_sfnt_off0001a994.bin
f86f23676c6a74d0d235f88ae8e2363c2f220ef061f7fac681ee5a1909443c50
pdf-font-stream PDF embedded font (sfnt) at offset 0x1A994 17664 bytes