Malicious PDF — malware analysis report

Static analysis result for SHA-256 02540925caf9ad67…

MALICIOUS

PDF

75.2 KB Created: 2021-09-01 02:48:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 259bc31526626d15986d6656696f1002 SHA-1: 2599e88b12527b675b789d4f64b82b246b743b90 SHA-256: 02540925caf9ad67f0603d25a73caa286dc84f97441c817eaf49ed4a8a17ea03
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. The heuristics indicate the PDF acts as a link farm, directing users to compromised CMS uploads and disposable hosting sites, likely for phishing or malware distribution. No scripts were extracted, but the presence of numerous external URLs suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://pistant.ru/uplcv?utm_term=grid+connected+photovoltaic+system PDF link annotation
    • http://cngwalk.com/fckeditor/userfiles/image/rejadusakejebixukav.pdfIn PDF document text
    • http://globalroomplus.com/bot/ckfinder/uf/files/9227411189.pdfIn PDF document text
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/5h4f037j2mbqnv9gs96p71f7t7/63861970768.pdfIn PDF document text
    • http://amon-syotengai.com/userfiles/file/4309832641.pdfIn PDF document text
    • http://dmkert.hu/files/file/dodemag.pdfIn PDF document text
    • https://mattress-leader.com/media/zitibipinisapivuwogu.pdfIn PDF document text
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/e4c6a3c8ecfb074aee6dedda7fc8e841/77669088494.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/tizulesubi.pdfIn PDF document text
    • https://restavracia02.com/userfiles/file/1579990308.pdfIn PDF document text
    • http://neoneofytou.com/ckfinder/userfiles/files/zanikagoxezedinojarufok.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a952ceba7---zezekojumowetulujimo.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d97eea45f49---gujulifonagu.pdfIn PDF document text
    • https://vigiweb.cl/dinamicos/files/file/rezilovukavadib.pdfIn PDF document text
    • https://matrainagycsalados.hu/userfiles/file/baganureguvomotijezapow.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/160da8f75bbabd---gesamizijigidolizosipesar.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/eimlsjp1um8fn3cc8c32iphmtr/59876988419.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160907d4b42154---61038219653.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/sesoxe.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/49369826506.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/torirasavixesikokov.pdfIn PDF document text
    • https://maintogelonline.info/contents/files/67972683182.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/89555929197.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/gutivakurogiwuzevu.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b70d407f45---99018319168.pdfIn PDF document text
    • 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_off0000c244.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC244 10996 bytes
SHA-256: 19fd9753df7b970bfaac66d12dde387e8fcc5ce25e4c0eac6c0ba34ee06fa117
font_01_sfnt_off0000dba9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA9 17036 bytes
SHA-256: b81357ea500d556bee325901e78b95b3a434c57f299db94f628cc6bccb38561f
font_02_sfnt_off0001076f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1076F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1