Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb114b8e5d12b5f5…

MALICIOUS

PDF

77.0 KB Created: 2021-09-09 22:50:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 83f5c6e413ba2911e99f8a212e7a2ed5 SHA-1: 72bdca6b231b14ab46f468348a4a7a409862c421 SHA-256: cb114b8e5d12b5f5d7f4eeceeee24f40056e4903402c6885c243a8c644e6e1b5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The embedded JavaScript is a common technique for initiating malicious actions within PDFs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://resurrection-life.net/userfiles/files/75442850889.pdf In PDF document text
    • https://artbynela.com/uploads/file/37914042048.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136b0bbbace8---giwupasaz.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136f40ebd934---ruduloduwabaloke.pdfIn PDF document text
    • https://moiatakashta.com/userfiles/file/90089860183.pdfIn PDF document text
    • http://zzfcw.com/file/fkimg/file/93770075960.pdfIn PDF document text
    • https://pvcmikser.com/upload/files/28767542026.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/tezeladuxulurinenowowalin.pdfIn PDF document text
    • http://pazzo.jp/js/upload/files/7974930526.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/73663795448.pdfIn PDF document text
    • https://polaria.cz/images/file/mapupegov.pdfIn PDF document text
    • https://ivanamihic.com/files/zumudufudud.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210905_0037F5D106CAAF8D.pdfIn PDF document text
    • http://ordinate-ltd.com/file_media/file_image/file/66165356083.pdfIn PDF document text
    • http://citra.cl/userfiles/file/savexubugezaluxuxof.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/59147466901.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/32306150320.pdfIn PDF document text
    • http://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3ad60df96---49393524835.pdfIn PDF document text
    • http://2013.letnifestiwal.pl/ckfinder/userfiles/files/73288494622.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-4/20210904202512847175.pdfIn PDF document text
    • https://digireg.si/upload/tujasapiwepizolame.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=undertale+addon+minecraft+pePDF 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_off0000c701.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC701 18336 bytes
SHA-256: f1caa4138666d728cfe0013bb2cd2f865bc378eb1fa11492b745ae78aa6228d8
font_01_sfnt_off0000f62a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF62A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E41 10620 bytes
SHA-256: 32d32318db04bda99f4a07e48a20466ccb69b45503ef319a6ec66435dcd3c432