Malicious PDF — malware analysis report

Static analysis result for SHA-256 18f2d3fd55edbf65…

MALICIOUS

PDF

70.2 KB Created: 2021-05-05 12:44:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 850e95dee447809f635cec5008e4da90 SHA-1: b7772686cf19158b8194dafb58309b0a95fa3f88 SHA-256: 18f2d3fd55edbf654592ef66f53b992760cd12e0f36b3ff6467255105c236e48
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links pointing to compromised WordPress sites, suggesting a link farm designed to host and distribute malicious files. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9576

Heuristics 7

  • 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.
  • 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 https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609062703ebd6---xoduruvaweteniterenebenu.pdf In PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073484800912---rowipanuso.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16077869da2bf1---8990473242.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608371cd0c556---velewo.pdfIn PDF document text
    • http://ahchala.com/img/file/68490059061.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/160856d2b992c2---40473482090.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c774c42112---95703998734.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/opmuo95erpflkn45n4qvq92058/31955597302.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/fobax.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160725fcca7d57---36659172238.pdfIn PDF document text
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/t30siici5ens7aclodd37h8cr4/jisok.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c737709d2---lulokovijadidenu.pdfIn PDF document text
    • https://gdr.co.il/wp-content/plugins/super-forms/uploads/php/files/2dd783fec5c3c54bede7adfa3d56a73f/7124279168.pdfIn PDF document text
    • https://www.siemers-deutschmann.de/wp-content/plugins/super-forms/uploads/php/files/6ev7jud6evme4su7p57s9o9nr2/gojopotazatim.pdfIn PDF document text
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/c50bb845ce5f1c2291b019dd8b7ff60e/96455224570.pdfIn PDF document text
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/5e3phtrti9id1463f6n4i7cgn8/tuxatiganapap.pdfIn PDF document text
    • http://amdind.com/userfiles/file/teleputopinuwu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=carrier+logo+vector+freePDF link annotation
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE1D 4836 bytes
SHA-256: 0115ee37373bd5361702bcd7d1c886929a268152e105e6bed080c2481b613ab8
font_01_sfnt_off0000eea8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA8 11232 bytes
SHA-256: 1478e6657b9a579ba5f86cf6e927df738abc09751a2b8bd63bdf29bf91a4f754