Malicious PDF — malware analysis report

Static analysis result for SHA-256 2cd4031434142515…

MALICIOUS

PDF

72.8 KB Created: 2021-09-16 21:56:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f4fcf970d378e2b4b1750ecec5c7f69f SHA-1: 2947ccc5d0f827ffdbde3013bea317cf3d9598b3 SHA-256: 2cd4031434142515c4cb9e68b94cd9578764f8bb3e53415432216992d14c4ff8
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a large number of external URIs, many of which are part of a link farm. The ML classifier and ClamAV detection strongly indicate maliciousness. The presence of embedded JavaScript suggests an attempt to execute code, likely to facilitate further malicious activity such as downloading a payload or redirecting the user to a phishing site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://gorsilawfirm.com/userfiles/file/bupalixe.pdf In PDF document text
    • https://hophamthaibinh.com/upload/files/vujemarabu.pdfIn PDF document text
    • https://www.alitec.es/js/ckfinder/userfiles/files/nezutuniwigimumubikog.pdfIn PDF document text
    • http://telektrans.hu/editor_up/46598559093.pdfIn PDF document text
    • https://dildendilecevirievi.com/upload/ckfinder/files/49033226660.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/ldfsqhddfvc4eo7ck2enc8gjog/3079282549.pdfIn PDF document text
    • http://jjburgerut.com/uploads/files/powofukixowe.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/5bbada26dc534923d9088da5c4f1a2ec/tefefafirogakemavup.pdfIn PDF document text
    • http://96stone.ru/userfiles/file/kexawavefunewodimoxul.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/xuxamoroxopamutuwaburodag.pdfIn PDF document text
    • http://e-baze.lv/images/site/file/91136881277.pdfIn PDF document text
    • http://execdentalclinic.com/uploads/ckfinder/userfiles/files/7018694859.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2cd73b3bb---58363839981.pdfIn PDF document text
    • https://maintogelonline.info/contents/files/97566741499.pdfIn PDF document text
    • http://galerie45.com/userfiles/file/90311153429.pdfIn PDF document text
    • http://jrecchina.com/ckeditor/ckfinder/userfiles/files/87230380846.pdfIn PDF document text
    • http://jatechkj.pl/upload/fck/file/voxobonepetege.pdfIn PDF document text
    • https://ceccarmaramures.ro/userfiles/file/96097170280.pdfIn PDF document text
    • http://the-bom.kr/upfile/files/pukisirumufu.pdfIn PDF document text
    • http://clubesquilacoma.com/uploads/files/molixodalodinavofes.pdfIn PDF document text
    • http://balletpanov.com/uploads/files/58426342148.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=gta+5+apk+and+filePDF 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_off0000bc73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC73 16140 bytes
SHA-256: b7f3c7c4a818a4bacdf544593e03e834f8c9b9a10d9a210fe7702075a6e2a353
font_01_sfnt_off0000e5e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5E3 10368 bytes
SHA-256: 4e3bd4b53b7a3dada24a90c216e056650f0b2d535e2161fd2b100a3cc619eaa0
font_02_sfnt_off0000fd83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1