Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c96920f617a3f6a…

MALICIOUS

PDF

69.5 KB Created: 2021-09-26 04:21:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b1c959807310c81c33925f468d388543 SHA-1: 47ac42606fe5b1cdd3f01287c21706cdb9bf41f1 SHA-256: 1c96920f617a3f6a51455f2b04e6bf12121498b9623fa9e1150bdce1b269a0f5
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a large number of external URLs, many of which point to compromised websites or disposable hosting, indicating a likely phishing or malware distribution scheme. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • 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 https://philabc.ru/uplcv?utm_term=why+my+apps+keep+stopping PDF link annotation
    • https://guapa2.com/admin/fck/file/82132629787.pdfIn PDF document text
    • http://dienlanhlongan.com/upload/files/88861414520.pdfIn PDF document text
    • http://lamardaegu.com/upfile/user/file/38002171656.pdfIn PDF document text
    • https://derfo.info/resimler/files/25344449098.pdfIn PDF document text
    • http://ilyxrace.com/userfiles/files/38954967531.pdfIn PDF document text
    • https://drnanemilk.com/tctt/sites/aaa/file/81181813851.pdfIn PDF document text
    • http://maezawa-jidousha.com/js/upload/files/63046934215.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/ulc0q5ovenk3l4oa554m387ihv/47570144054.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b8bc28a305.pdfIn PDF document text
    • https://menu2uplus.com/images/file/13022392769.pdfIn PDF document text
    • https://www.ojchamber.com/ckfinder/userfiles/files/jesimuwagesus.pdfIn PDF document text
    • https://chanty.dacola.com/upload/files/mosedejebutivuk.pdfIn PDF document text
    • http://www.smpnuenen.nl/images/files/69218217465.pdfIn PDF document text
    • http://haciogullari.com/depo/sayfaresim/file/doposiwum.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/ce2f28a1a7b64b5544c8dd5ccdfe0fb6/86831993773.pdfIn PDF document text
    • http://veterky.ru/ckfinder/userfiles/files/8230485759.pdfIn PDF document text
    • http://thanhlapcongtykiengiang.com/upload/ck/files/95953219146.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/1110595765.pdfIn PDF document text
    • https://icon-studios.com/userfiles/file/41118088821.pdfIn PDF document text
    • http://nakajima-ya.com/upload/save_image/files/11910331988.pdfIn PDF document text
    • http://droneducational.com/admin/userfiles/file/gubizudanojagetijuzu.pdfIn PDF document text
    • https://apteka-wratislavia.pl/halatecza/userfiles/file/xajisexiwilexasorowobow.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_off0000ae44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAE44 16644 bytes
SHA-256: 5881cf53bcfde089184e974d130a5be7fed9dbc3d11f4cccee75a027afff472e
font_01_sfnt_off0000d821.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD821 10752 bytes
SHA-256: 0bdb64636b310a7aa9a351eb0952dba6fd5e4fe8ff41f3186ddee71999e9cc57
font_02_sfnt_off0000f0c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1