Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5f453415786c924…

MALICIOUS

PDF

76.0 KB Created: 2021-06-26 14:03:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: c0c43591b4dacedf2c610fb8e8714232 SHA-1: e53ef8fb583ba53e0b415f1e9708dfa875f17fea SHA-256: a5f453415786c924fb64dd97fef6e4b82c47964c7d1b00af34dacf1bef34635a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many pointing to compromised CMS upload directories, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. No scripts were extracted, but the structure and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://systematix.pl/userfiles/file/91480934981.pdf In PDF document text
    • https://gachbinhduong.com/upload/file/99573879075.pdfIn PDF document text
    • https://jfefood.com/wp-content/plugins/super-forms/uploads/php/files/abc3d1ddbdda85010fec0dc441f1ed3b/dalusaruxalafatovisajawo.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c94d7c04abe---49109346951.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a8fc3cec770---94239037612.pdfIn PDF document text
    • https://exporoaster.com/app/webroot/files/images/pages/files/58107570096.pdfIn PDF document text
    • http://josephpowellfamilyreunion.com/clients/0/04/04c15d356d3082020e114f8c0300f46e/File/78078447065.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609cc12b666fc---xejofo.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/dipivetubitezoma.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/160785bc791f6d---34363761902.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/nugunomopogemolugokofepij.pdfIn PDF document text
    • https://actor-conseil.com/files/file/nedozevosowisuge.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085f2ffb3303---11678062001.pdfIn PDF document text
    • https://designclarf.it/file/jitekutitenupikofazope.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/db37a7aa32afd53bccd88dac2fab8af4/82052552088.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/a0e7c32979d0f08601437a92bc113e53/razojobed.pdfIn PDF document text
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/55025065588.pdfIn PDF document text
    • https://pluviaterra.mx/wp-content/plugins/super-forms/uploads/php/files/2ce2d09608f5d1f4640ea31fbfd6d2f9/70495940319.pdfIn PDF document text
    • http://drairtools.com/ckfinder/userfiles/files/momujexibukogogotetuk.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/rls15tssf86ml3vbfi6e8conq1/pazifasujovokeburowaw.pdfIn PDF document text
    • http://alphabodysupplements.com/newerac2c/userfiles/file/94529635496.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e4864f489---11659682456.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9a9ba7d8c3---bixapebud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=2+syllable+words+that+start+with+cPDF 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_off0000c799.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC799 16208 bytes
SHA-256: 9ecf740b12212b9f929729cdf3921631a99637179e7e2eaa1398eb8fd9979e76
font_01_sfnt_off0000f1bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BF 10724 bytes
SHA-256: 1053756aece704600e1342111004823f1c4cf98fceaadf6fd4020521f696ebd4
font_02_sfnt_off00010ab3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1