Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef681ab0fd9793a6…

MALICIOUS

PDF

79.6 KB Created: 2021-09-04 06:22:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 98fc05c62ab6bcc46fd876cd85a8ba72 SHA-1: 951fbcd8fa8007b742c98d5d6717b41269783675 SHA-256: ef681ab0fd9793a67c864cffef4be16f5cf80d148169a0519637a03476263172
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a phishing or redirection scheme. ClamAV and ML classifiers also flagged this PDF as malicious, specifically identifying it as a phishing trojan. The embedded links are designed to lure users to external sites, likely for further exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • 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.
  • 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://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac89b24a515---nudisodalafebajimoxase.pdf In PDF document text
    • http://makesrealsense.com/ckfinder/userfiles/files/17824726390.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b53698249---72238382572.pdfIn PDF document text
    • http://barrospizzadb.com/uploads/files/ruxorepunemuseke.pdfIn PDF document text
    • http://naphogacomposite.com/upload/files/mejoxixisiwirubu.pdfIn PDF document text
    • http://bigxra.com/uploadfile/file/2021051023320373499.pdfIn PDF document text
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/bd068f331db0cb4d5c625ac765546bd5/jilesawewobonipija.pdfIn PDF document text
    • http://www.olivier-frey.ch/user/web/file/kusokodasowapedilo.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b07084b316c---72437074315.pdfIn PDF document text
    • http://grupposcorcia.it/userfiles/files/79243597999.pdfIn PDF document text
    • https://myvideoclasses.com/ci/userfiles/files/88864228290.pdfIn PDF document text
    • https://melz-feu.ru/upload/vigipixodobosatodigok.pdfIn PDF document text
    • http://lucann.com/Upload/file/14036100299.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086c10f254e6---92115948706.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160faf90ae6767---vewolasubul.pdfIn PDF document text
    • http://roxburyhs1987.com/clients/63080/File/43733146210.pdfIn PDF document text
    • http://zatexpress.com//upload/userfiles/files/worutijanurugijigegasepi.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/3a2f8698cbc78c8c0a114ebc39d48a29/nojukesazasej.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1608e527e33096---95969694757.pdfIn PDF document text
    • https://goodline.by/userfiles/file/lomobefuzajiwi.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d4c6378f3fe---49581286071.pdfIn PDF document text
    • https://cleaner.pl/userfiles/file/kipabu.pdfIn PDF document text
    • https://ozmutludokum.com/userfiles/file/44661077392.pdfIn PDF document text
    • http://villaroyalenews.com/userimages/35693075174.pdfIn PDF document text
    • https://topclassgardening.nl/images/file/wubiju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=jurnal+politik+di+malaysia+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d191.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD191 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e9a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9A3 17908 bytes
SHA-256: d3123e42d727fbb8318dad4937596c379a98816c664212405506b444dbb19979
font_02_sfnt_off000117ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117AE 10824 bytes
SHA-256: 20cffdd4f7fa82cd5784b19d9eb85f0fc70b6236f147e782fc60890e5931d21a