Malicious PDF — malware analysis report

Static analysis result for SHA-256 d428045d1d58ca00…

MALICIOUS

PDF

81.5 KB Created: 2021-09-13 13:31:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7dbf4fea5ceac1ac98aa14818553e8a3 SHA-1: cb6a42ad3c03160f7c6a8994d570b432f99d463e SHA-256: d428045d1d58ca0009a24a0ba75d491558cd09dcd966acc6e839b75235cc0278
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified the document as a link farm, with many URLs pointing to compromised CMS uploads or disposable hosting domains. The presence of multiple external URIs suggests an attempt to redirect the user to malicious content, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://ddshower.com/ckfinder/userfiles/files/kifubofumadegajej.pdf In PDF document text
    • http://srs-budapest.hu/uploads/files/7020819867.pdfIn PDF document text
    • https://smartbrand.ro/mm/file/kewibagoxosunomin.pdfIn PDF document text
    • http://articolo17.it/siti/usr/foto/files/53268482974.pdfIn PDF document text
    • http://cafehinglung.com/uploads/files/xoxujemarep.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16135045c3e799---pukopaponidivafeti.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613203b720154---16642388373.pdfIn PDF document text
    • http://hnsunnyfood.com/d/files/43332688585.pdfIn PDF document text
    • https://cmoretv.com/userfiles/27679938412.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/44632432595.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/sawamerizu.pdfIn PDF document text
    • https://coffeetuanvang.com/Images_upload/files/tufagebarudatavarababiwa.pdfIn PDF document text
    • http://ailizia.com/userfiles/10402697021.pdfIn PDF document text
    • http://kastely-vacduka.hu/fileok/file/80277001562.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/161394dae1b0dc---56214286964.pdfIn PDF document text
    • http://ch-yang.com/upload/files/6815694216.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/91508625201.pdfIn PDF document text
    • https://basisnomor.com/contents/files/sivajakaratekonuzi.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1914042eb---gemasutagetuta.pdfIn PDF document text
    • http://mynotary.ca/sites/all/sites/mynotary.ca/files/setenibo.pdfIn PDF document text
    • https://nhabe.com.vn/ckfinder/userfiles/files/dizewezepe.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210909185922823.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/vufenonebarumotax.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=damon+salvatore+live+wallpaper+iphonePDF 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_off0000d44c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD44C 10668 bytes
SHA-256: caf6cb2b9a12de1312a5e25c0052638c1cad0a8d143ef5b381f5794740a85806
font_01_sfnt_off0000ec91.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC91 19800 bytes
SHA-256: a9a3743ead728f9dfecdef4bd1b57a978403f61ca4e697b091a79e51c33d8e96
font_02_sfnt_off000120d2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120D2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1