Malicious PDF — malware analysis report

Static analysis result for SHA-256 9113b77973d30ae5…

MALICIOUS

PDF

83.1 KB Created: 2021-09-16 01:45:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e5c9027115092b3ce640945faed2b603 SHA-1: 9f8ba4e7880bcf55733ebc993ecd6f6150a9ed47 SHA-256: 9113b77973d30ae50cf8010967cd293f72bfeda369c86c21de48a9bb75b86b4d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are identified as link farms on disposable hosting or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://synerhu.ru/uplcv?utm_term=android+games+on+chromebook PDF link annotation
    • https://aquatrustfina.com/userfiles/file/50741570837.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/tenurirudimaxedu.pdfIn PDF document text
    • http://tongshengchem.com/ckfinder/userfiles/files/85373207422.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/zuvojometixizi.pdfIn PDF document text
    • http://mertcelikkapi.com/userfiles/file/16056212755.pdfIn PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/temero.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613d6dceb3c02---fejiritavajilona.pdfIn PDF document text
    • http://guerrazzi.info/userfiles/files/vuvofi.pdfIn PDF document text
    • https://archielectronics.com/userfiles/files/daxikufori.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1614273b096fe1---ninebuvafewawesomoke.pdfIn PDF document text
    • https://agape4u.org/userfiles/file/ravetepumobopedumefiji.pdfIn PDF document text
    • https://foodexgida.com/uploads/files/41901038329.pdfIn PDF document text
    • http://conganbacgiang.vn/app/webroot/uploads/files/11726198250.pdfIn PDF document text
    • http://aptekadc.pl/userfiles/userfile/36070188903.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/459ac3a106ad2d8a8c2a707b65679200/86589398116.pdfIn PDF document text
    • http://dermalab.pl/userfiles/file/51036313412.pdfIn PDF document text
    • https://jin-hung.com/userfiles/file/pelufozelapavelafinin.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef47419d24---36792660116.pdfIn PDF document text
    • http://gtlmarinefuel.com/userfiles/file/1102846621.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/sulavis.pdfIn PDF document text
    • http://jinyezi.cn/upload/dizudi.pdfIn PDF document text
    • http://mskgroup-spb.ru/upload/file/58592621769.pdfIn PDF document text
    • http://tongshengchem.com/ckfinder/userfiles/files/11874300574.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_off0000e084.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE084 10884 bytes
SHA-256: c48300aa8c9d4d503d9a69bc39549fdf9e7b50307e4dc9114befcbf541b80832
font_01_sfnt_off0000f944.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF944 17684 bytes
SHA-256: 83a5fea65b360d092822672325a6974fe715985cac7de177e9d6a8cafdc40e84
font_02_sfnt_off00012719.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12719 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1