Malicious PDF — malware analysis report

Static analysis result for SHA-256 987d77ce7aff411d…

MALICIOUS

PDF

97.7 KB Created: 2021-09-07 12:47:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3ceb9b7dc9f2a55e6051b3c3dcf67323 SHA-1: 820c38f33747e087af655cd8cae3f6ea709f66e4 SHA-256: 987d77ce7aff411deb66c48fed618186582aaee09b08e4a2af41c1c678596dea
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple compromised WordPress sites hosting further malicious PDFs. The presence of a 'Password-protected archive handoff' heuristic suggests a multi-stage attack where the user is prompted to obtain a password for an archive, likely containing the final payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9875

Heuristics 7

  • 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.
  • 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://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/a8d8d2bc22b64a1f71f3e186268d5195/bamosilujuno.pdf In PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/f092ef87cba57863895726edc1c7d10d/82484053693.pdfIn PDF document text
    • http://kibbkw.com/uploads/file/rupilisutivezizo.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/c7c05f84eb17e05d2e252e00b2a64e85/natinopaxinar.pdfIn PDF document text
    • http://share-world.tw/userfiles/file/85299974708.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8226ea0b8---78000046644.pdfIn PDF document text
    • http://royalgroup.at/tmp/71977444588.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1f805432e---raradoxojala.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/cb92b257b9faba25b438ca6d0e712184/20184195190.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a46a9918d8b---58549942988.pdfIn PDF document text
    • http://ztkammer.at/uploads/file/ginekoruzewogezajojim.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/27507060373.pdfIn PDF document text
    • http://cochemical.com/upload/files/84142092308.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/gixijasudukesarex.pdfIn PDF document text
    • https://cor.org.ar/wp-content/plugins/super-forms/uploads/php/files/a6gtk2jakgv1v1s76fcin71pt7/nazunumu.pdfIn PDF document text
    • http://straub-online.ch/userfiles/files/99152947636.pdfIn PDF document text
    • http://gloria-eurex.com/images/blog/file/wadabozovidibilimagebit.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/81h0hlb8hq01uf8qdobo8lojv5/sinelefopagilofe.pdfIn PDF document text
    • http://sevimticaret.net/userfiles/file/54958557379.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160850c65e894e---mekafimedulug.pdfIn PDF document text
    • http://eros-arena.com/eros/userfiles/file/18207893956.pdfIn PDF document text
    • http://worldofpacifiers.com/editor_uploads/system/files/78731433110.pdfIn PDF document text
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612b41762f5db---bofinazetino.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/66270155815.pdfIn PDF document text
    • http://automozg.by/upload/editor/files/73945965814.pdfIn PDF document text
    • http://vantaidongsaigon.com/uploads/files/vimaneduruvanixuvuwo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=java+core+interview+questions+and+answers+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_off000113a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113A3 10956 bytes
SHA-256: 718e4edac27cd475981e634e3940b4dfe2c1e9175ee8b357a8930f41d06710d9
font_01_sfnt_off00012d0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D0E 19488 bytes
SHA-256: 7d5c44144bd78d5acfcbeebfa9b2a7da3bfb4a50c195b39d54a03d8211e4e919
font_02_sfnt_off000160a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x160A5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1