Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8613286000f95c8…

MALICIOUS

PDF

70.6 KB Created: 2021-09-24 17:53:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 57e5e14291da814dca152d0e382f2eb8 SHA-1: eb73dfa77e767117ca76cced6c3157390710b38d SHA-256: a8613286000f95c8cd4f6f31b37ed533e66a848a9ed9c24f2d022419a19533c9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting and are structured as link farms, indicating a likely attempt to redirect users to malicious sites. While no scripts were explicitly extracted, the nature of the URLs and the heuristic firings suggest a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://irlanc.ru/uplcv?utm_term=top+down+android+games PDF link annotation
    • http://xn--b1afbmo0alc.xn--p1ai/ckfinder/userfiles/files/65420537022.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/bevamiragevinuxovamode.pdfIn PDF document text
    • http://wimborst-ceramics.nl/public/view/upload/fckeditor_images/file/42984137984.pdfIn PDF document text
    • http://janaturismointegrato.com/uploads/file/ridovodetegozokuved.pdfIn PDF document text
    • http://srtprogetti.eu/userfiles/files/79009678529.pdfIn PDF document text
    • http://spain-ex.com/images/blog/file/xedifulusam.pdfIn PDF document text
    • http://poliinc.com/upload/files/57021600630.pdfIn PDF document text
    • https://stichtingech.org/ckfinder/userfiles/files/vixexelatatos.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/252230395fa0dfe0b45e1b7d02dd91f2/bomajedule.pdfIn PDF document text
    • https://mmeasar.com/mmeasarfiles/file/lunakujowomexogedufe.pdfIn PDF document text
    • http://electric-kernbichler.at/5713421043.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/58738671462.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/16684350601.pdfIn PDF document text
    • http://diadiemvui.com/upload/files/65670126315.pdfIn PDF document text
    • http://zekejozsef.eu/FCKfeltoltott/file/60554296553.pdfIn PDF document text
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/t0an6ojlhfbq7770mihg36694r/tosexus.pdfIn PDF document text
    • http://detskaoptika.cz/ckfinder/userfiles/files/winugexo.pdfIn PDF document text
    • http://neoneofytou.com/ckfinder/userfiles/files/69518601875.pdfIn PDF document text
    • http://syntrend.critical.tw/upload/files/61071330557.pdfIn PDF document text
    • http://influences-vegetales.eu/assets/Image/files/50905828589.pdfIn PDF document text
    • http://zenkatsu.dk/files/damaxitijifebixil.pdfIn PDF document text
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/52617710669.pdfIn PDF document text
    • http://dzstock.com/Upfiles/file/65343138433.pdfIn PDF document text
    • https://mbbs.hr/files/mitabunebobanotumabeg.pdfIn PDF document text
    • http://cermak-expo.cz/data/files/file/tuzoxobopomal.pdfIn PDF document text
    • https://underworldgear.com/upload/users/files/55705497025.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_off0000b193.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB193 16964 bytes
SHA-256: f05833986aa34383b606bfa6fe97d62088669161191c24b4a54a3a47d96dc909
font_01_sfnt_off0000dcd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCD2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f4e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4E9 10640 bytes
SHA-256: 47d014aeaa83d894e336835d3ed138ebae9a76b8bdbf8970f5ea4262f81dec2c