Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb5ed909c021cec1…

MALICIOUS

PDF

73.7 KB Created: 2021-06-23 23:31:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: feaddbc31fcb1883fba053f7e3bcc6a0 SHA-1: ccb375d4b58153ae408251f0889d713f71a9a400 SHA-256: fb5ed909c021cec10180f7558bab46db910b551229e7c3817db2e83f001ad8cb
196 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to potentially compromised WordPress upload storage and other disposable hosting sites. The primary malicious URL identified is http://developmentassociationofnagaland.org/nbloom/fckuploads/file/lezaduwixibefa.pdf, which likely serves as a lure to download a secondary malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://arichaindia.com/userfiles/file/medaxi.pdf In PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/cd20771f45e755b0182c7f46b9b16ba1/nedel.pdfIn PDF document text
    • http://anhuishangbiao.com/upload_fck/file/2021-5-4/20210504100420580942.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b70c949a56---josalanapoputexume.pdfIn PDF document text
    • http://aweibel.com/Photo/file/mepunadovovunaw.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b135d180194---18040680449.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160706c60e2ee3---sobek.pdfIn PDF document text
    • http://chickenwild.com/upload/contents/images/images/jorevinijuvoditimeke.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c8ce15804fe---73056951359.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/6e7349213017c341d82c1fbc19bafee9/farafebonumorujafufidepux.pdfIn PDF document text
    • http://big-blue-bus.com/pics/fotos/1/file/xopibodurod.pdfIn PDF document text
    • http://sxhk365.com/uploads/file/%5C/58769753568.pdfIn PDF document text
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abdf157016f---67583636161.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160791c4fdb50c---bomoxe.pdfIn PDF document text
    • http://developmentassociationofnagaland.org/nbloom/fckuploads/file/lezaduwixibefa.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/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=easy+trivia+for+kidsPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE238 5052 bytes
SHA-256: a5b3f786a29609ba3b73b56d9bfcf42d4958516432120daeb19f5396c2cf1863
font_01_sfnt_off0000f38a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF38A 11256 bytes
SHA-256: bfec182457b6a841ccfb00b911cf726694cc14ae22598a68c930b8ce76fa480a