Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad57c70731d225e8…

MALICIOUS

PDF

72.0 KB Created: 2021-09-17 11:10:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5532fb139f4fce0d143499209c1c4fef SHA-1: db69893289ad307c9e9e4c9392a875461555b8bc SHA-256: ad57c70731d225e8619322099c691ba3689d8f79203c4f28880b6cfba1ea07b6
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many embedded URLs pointing to various domains, some of which are hosted on compromised CMS uploads. The primary purpose appears to be directing users to external sites, potentially for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://firsatpin.com/calisma2/files/uploads/54855147510.pdf In PDF document text
    • http://influences-vegetales.eu/assets/Image/files/29974437120.pdfIn PDF document text
    • https://videoeffect.ir/data/file/joxagibilokaxawipovawi.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614048f7076a6---44797472161.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/3643602203.pdfIn PDF document text
    • https://umutfm.com/resimler/files/gokitupif.pdfIn PDF document text
    • https://granitnet.hu/editor_up/gunivovojuto.pdfIn PDF document text
    • http://kelkenaghshband.com/app/webroot/img/files/nixedopopipiboritabam.pdfIn PDF document text
    • http://meuble-tunisie.com/userfiles/file/40809978910.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/161363e9eb3b12---22882138332.pdfIn PDF document text
    • http://omnoiptv.com/outscapes/admin/ckeditor/uploads/ck/files/bomezaneranodowol.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132f57b32db7---6097008312.pdfIn PDF document text
    • https://annekienlen.fr/imagesfile/33671232481.pdfIn PDF document text
    • https://delaneyllc.com/ckfinder/userfiles/files/sojutasezoxo.pdfIn PDF document text
    • http://beauty214.com/uploads/files/202109110101502607.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e6e4311f4e---89403317128.pdfIn PDF document text
    • http://bon-mar.com/fck_user_files/file/84176038419.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/7e9682d85eddf6453e3ad04acc77af94/43219171654.pdfIn PDF document text
    • http://ecompletecontact.com/ckfinder/userfiles/files/fibiwumumopefu.pdfIn PDF document text
    • http://fortwashington.abwingsmd.com/uploads/files/dozakamebivanuz.pdfIn PDF document text
    • https://publicbridge.pl/userfiles/file/36634994220.pdfIn PDF document text
    • http://www.oe.com.tw/ezadmin/ckfinder/userfiles/files/wuwironojufamiduroji.pdfIn PDF document text
    • http://fueandhair.com/userfiles/files/59256105959.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/gakumogakojawim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=asphalt+8+mod+apk+pcPDF 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_off0000b6cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cee2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEE2 10632 bytes
SHA-256: 1d0357f87df203c4b4d4763f5222d4a96ac4361ae59a53c01a27e9f0129d8340
font_02_sfnt_off0000e755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE755 17104 bytes
SHA-256: f6c40872983e34827b20476c108f03050309efdd86b01582314c01bf23ba816b