Malicious PDF — malware analysis report

Static analysis result for SHA-256 13aa8ae6866999d5…

MALICIOUS

PDF

92.0 KB Created: 2021-09-04 06:15:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 03a7c4a4a68493c88431a07ef5014d12 SHA-1: c6d491eb85906b102f35f11bba285d64904ff0d3 SHA-256: 13aa8ae6866999d575d2d82247fb5b6dda9aac8599e260b1ccf26a756e543bcb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised CMS upload directories, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware distribution campaign, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 6

  • 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 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://dioceseofniranam.org/userfiles/file/wavavorerokekure.pdf In PDF document text
    • http://bioterapiazabiegi.pl/obrazy/file/jiwuj.pdfIn PDF document text
    • http://france-ex.com/images/blog//file/7988752102.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/71b7e959fae9231ca9459270e3185704/migofivutupazesi.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a98f183750d---xetipomemabiwef.pdfIn PDF document text
    • http://ct-tci.com/cttax/userfiles/files/57543119269.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/4a3978831a154c44fcf747491486b698/95634889818.pdfIn PDF document text
    • http://www.atrium-tuiles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd01d18a1d7---feboberopifo.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/21b9b39d30220c7700475f7715549ba8/84167447257.pdfIn PDF document text
    • http://85560891.com/upfolder/e/files/20210803010828.pdfIn PDF document text
    • http://www.bargiel.com.pl/ckfinder/userfiles/files/fowakagutozuzijuduz.pdfIn PDF document text
    • https://bdcomunicazione.it/file/55189989976.pdfIn PDF document text
    • http://robertoantoniz.com/resources/original/file/gefewiduwakupavamelokunir.pdfIn PDF document text
    • http://blbr365.com/userfiles/file/1628791051.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606feaaa72849---93594421895.pdfIn PDF document text
    • https://remont-bez-zabot.ru/files/file/81241805223.pdfIn PDF document text
    • http://xn--80aagkbrca3apkgkee0a1bi.xn--p1ai/ckfinder/userfiles/files/dolozepuzenax.pdfIn PDF document text
    • http://mkpstroitel.ru/upload/files/81501648199.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d02d62d96a---rajapoxekunuganeriveleze.pdfIn PDF document text
    • http://luckdidea.com/ckfinder/images_store/files/zibetuw.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160800c0073f10---guzul.pdfIn PDF document text
    • http://herfon-machinery.com/images/ckfinder/files/20210813001256.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16117d79cb520f---11657735637.pdfIn PDF document text
    • http://www.herbertvanderbrugghen.nl/draft/12901153686.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=research+articles+on+english+writing+skills+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_off0000ffd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFD5 18596 bytes
SHA-256: e4013b7b25c3e91486be647c8ff44a8a130a6e2fbb2edb4399be24655fc175fb
font_01_sfnt_off00013016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13016 11124 bytes
SHA-256: b13eabfeec733b88e286c35000e6b26338bf88801aed59358493f842f5d5bb01
font_02_sfnt_off000149da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1