Malicious PDF — malware analysis report

Static analysis result for SHA-256 4de105be8aa2d737…

MALICIOUS

PDF

92.5 KB Created: 2021-09-05 22:19:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0d3414a5734f9739b312ef512b1d39d7 SHA-1: 514981cb49027eb1ea365bccc51750fade451bb4 SHA-256: 4de105be8aa2d737a52007cbb2b971fc891f5fbab93bf61e90ee4ddfa65848d7
156 Risk Score

Malware Insights

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

The file was identified as malicious by a ClamAV signature and an ML classifier. It functions as a link farm, containing numerous URLs pointing to external resources. Several of these URLs are hosted on compromised CMS uploads or disposable domains, indicating a potential phishing or malware distribution scheme. The PDF structure itself does not contain executable content, but rather serves as a deceptive gateway to malicious external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://acryl-bg.com/userfiles/file/tanikazigisojowe.pdf In PDF document text
    • http://bocghedanang.com/media/ftp/file/63348863374.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/c4ae8d23ab1510220e608d3bf38d79ee/71909770619.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b244d2dd319---61253670010.pdfIn PDF document text
    • http://ipublicity.cz/data/file/27933849889.pdfIn PDF document text
    • http://primebrokeragetx.com/ckfinder/userfiles/files/lizig.pdfIn PDF document text
    • http://jrmhandling.nl/upload/file/jivalinonul.pdfIn PDF document text
    • http://kledingindex.nl/images/uploads/50478645577.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/muverozanojefojisob.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/zirobikonobinulozafeziser.pdfIn PDF document text
    • https://namphuctourist.com/userfiles/file/rekinutoxise.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160716b2af3669---jumiloruwofagepij.pdfIn PDF document text
    • http://weiddy.com/uploads//files/202108130446071124.pdfIn PDF document text
    • http://sinoscaform.com/upload/ckimg/files/202108261103209185.pdfIn PDF document text
    • http://hgbs.de/userfiles/file/62829216514.pdfIn PDF document text
    • http://degrossier.nl/uploads/file/86244333008.pdfIn PDF document text
    • https://sinarwaja.com/account/files/nusikerukusa.pdfIn PDF document text
    • https://worldmedglobal.com/userfiles/files/35624434359.pdfIn PDF document text
    • http://mmdplus.com/userfiles/files/20210702_015136.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/21359420226.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/6e15fb2c9010e3206e7fada3122fe6e9/kezod.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=harpercollins+study+bible+student+edition+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_off000102ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102EE 18448 bytes
SHA-256: bdfeb7a16906a106c3203167e3cdf6d329fbb9642f0d1a7e360c58de43c99d65
font_01_sfnt_off000132ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132CA 10956 bytes
SHA-256: 19aa2c6f60bc72ac17eb70401d0052c0b5fee6b955111a2a96af94ac84daf207
font_02_sfnt_off00014c11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1