Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef72f74863e12df9…

MALICIOUS

PDF

100.8 KB Created: 2021-07-27 18:29:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 0eb0f17e5a780b584669b94858192315 SHA-1: ac733942b799925b98a347db5e85f5594cd2c065 SHA-256: ef72f74863e12df99f70c0892acd1fa912b8d52b9362570c84af507e73657006
156 Risk Score

Malware Insights

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

The file is a PDF identified as malicious by ML classifiers and ClamAV, exhibiting characteristics of a link farm. It contains numerous embedded URLs pointing to compromised CMS upload directories and disposable hosting, suggesting an attempt to distribute malicious content or phish users. The presence of multiple external URIs and link farm indicators strongly suggests a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://almuhja.net/ckfinder/userfiles/files/3013054803.pdf In PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc67324db3---32980702014.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/2acea9c1f05d5abb901bd9257a2ef192/69264616664.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078528a8cfa6---4966821153.pdfIn PDF document text
    • https://zlatartopalovic.rs//files/54426016158.pdfIn PDF document text
    • http://cloverpark1960.com/clients/1/17/17c242f0968dc4bce059666b43fbd075/File/43434032373.pdfIn PDF document text
    • http://www.publicitymailing.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16076e760dfebb---najutetukavok.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160821de58608c---jamiridezatigiriluse.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/7775050511.pdfIn PDF document text
    • https://turkuazhost.com/calisma2/files/uploads/varivas.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/2g0ndncfleho0sm4j9vvh8i4bd/nipakarapaduxinokujivopu.pdfIn PDF document text
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/d5d28435482e1a0630d12d78b19c567e/mimokazemimetuku.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/9da6ae5b966ce3de136d69d4ef2b593a/54585382829.pdfIn PDF document text
    • https://botroul.be/uploads/vikoxebuto.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607567c56b902---4845168776.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/losox.pdfIn PDF document text
    • https://telenovella-bg.com/files/4743473994.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/vsu3sp04a7hd8kh2u5rte351lq/wulagotedukofivunojugol.pdfIn PDF document text
    • http://peaceinsrilanka.lk/userfiles/file/lunajedujogafawibe.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160fedb7b0ab4a---kiradapogegativozajanuf.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=kit+vi%E1%BB%87t+nam+dream+league+soccer+2020+manchester+unitedPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011421.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11421 1740 bytes
SHA-256: 07af91d03519a0a505b73abf62652fd20379d1466922ebc21a500b9d7eefeb08
font_01_sfnt_off00011c5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C5D 20248 bytes
SHA-256: cf9ce78f151074c320fa15de26ed76a4ef4702954cfdc7701f8babdf506fc059
font_02_sfnt_off00014eff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EFF 11424 bytes
SHA-256: 711ffa4e57e5ad20490c285584883ec2a5a66489e6b49ad553b38250878e0fd8
font_03_sfnt_off0001694c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1694C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1