Malicious PDF — malware analysis report

Static analysis result for SHA-256 d99866d697ad3d38…

MALICIOUS

PDF

89.3 KB Created: 2021-06-25 14:50:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5438432a922aa2b41add5504c45c0c05 SHA-1: 2b0c431a0ad12443109657e1baef545fb5ea31de SHA-256: d99866d697ad3d386a5fd7cc328b2e3863856334e555a16fa33943618054d1d2
212 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a phishing lure, specifically using an invoice or payment pretext combined with instructions for handling a password-protected archive. While no scripts were directly extracted, the presence of numerous links to potentially compromised WordPress sites hosting PDF files suggests a distribution mechanism for malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 9

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d4e5256f22d---89508629353.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c121d8ed0a4---kerokitixewe.pdf
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/behfab2ugl28l8bepmv3dk4da7/kifajuwul.pdf
    • https://genesislighting.net/wp-content/plugins/super-forms/uploads/php/files/2221213930c2eb37218b5d620daf20f5/7105715322.pdf
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aafcfcde0f4---31412116599.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6bf0cbc8ab---rewizapap.pdf
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/grl58cdole87po2sotrc4nvu82/zavaxemi.pdf
    • https://euroroma-bg.org/files/file/58400948968.pdf
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8a5d0c3265---14290744656.pdf
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a3989e1ddb1---barapuzulo.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/90f3842ff27858643e8bb19ea3a5a4e5/74494029497.pdf
    • https://angelsstaff.com/uploads/file/53242005657.pdf
    • http://cortabellanews.com/userimages/93214906880.pdf
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/0437d27ba86e97bd2459a981c05a9d34/xofebizotejusipen.pdf
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608827c0e2242---73779716208.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=pdf+in+webview+android
    • 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_off0000f627.bin
574d60bf91fed420b4d4376641258c064ddcb09715b693e1331f581f309aa975
pdf-font-stream PDF embedded font (sfnt) at offset 0xF627 18496 bytes
font_01_sfnt_off000127b6.bin
52d85586c6befacab4179b2a7673e65a2e04dcf3c6774979385d88734333c2b5
pdf-font-stream PDF embedded font (sfnt) at offset 0x127B6 10328 bytes
font_02_sfnt_off00013f26.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13F26 16792 bytes