Malicious PDF — malware analysis report

Static analysis result for SHA-256 031c88698f24c073…

MALICIOUS

PDF

79.2 KB Created: 2021-09-01 18:21:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 6797059ab302dd9ce21a7a31f2926249 SHA-1: d1ccf9530a12d8c69bdc4ce0cae9ecf22c491e7b SHA-256: 031c88698f24c0736cf75647247af212b42a0631c51984854194402f813c3e12
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://npxbyy.com/wang3_3_10_27/Upload/Upload/file/20218231698071.pdf In PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160fd289e8f474---1473318007.pdfIn PDF document text
    • http://www.anjhimayath.com/upload/file/notakajokesukurir.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c918b4d9dbd---damegojaretozogokisasolez.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5408df405---73122923005.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a8386fdea---loxejegox.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/07eac99acaf16081bf6818ddf008722b/5079766940.pdfIn PDF document text
    • https://rajakeempat.com/contents//files/lupodedilopoj.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a35a65d55c8---2865033887.pdfIn PDF document text
    • http://hwayinn.com/image/files/20210731_215331.pdfIn PDF document text
    • https://vv-alc.nl/uploads/files/74133727165.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608295060da0a---nakiteridaf.pdfIn PDF document text
    • http://dmkaudit.sk/101/upload/file/19263158955.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606f5fd8d0cba---kuvepivopoji.pdfIn PDF document text
    • http://vocal.bpv.su/content/files/files/gabijadubiwefaxid.pdfIn PDF document text
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/047d44dfcd265632bd1bf93d86c9c04b/66653288979.pdfIn PDF document text
    • http://traviet36.com/upload/files/4845892318.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/wipewakup.pdfIn PDF document text
    • http://harmonie-avion.fr/actualite/files/58044817106.pdfIn PDF document text
    • http://asustainable.com/global/file/42355958255.pdfIn PDF document text
    • http://dhleisure.com/ckupload/files/kesipowulugelik.pdfIn PDF document text
    • http://taxicityplus.ru/userfiles/file/xodokowupozaxe.pdfIn PDF document text
    • https://coevent.ru/upload/files/jekiwoxebubadal.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=limited+wifi+meaningPDF 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_off0000d123.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD123 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e935.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE935 17572 bytes
SHA-256: 0bc54a9d6b32d48adb7e17a3aab360f4fe8715159077f8bc96a709ddd519ac9e
font_02_sfnt_off0001171e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1171E 10304 bytes
SHA-256: a7cdbe36320898e0bc2e512092fe5f685bf72c3ae24c8b019cda002473e682af