Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b8355b753af1f6e…

MALICIOUS

PDF

93.7 KB Created: 2021-07-31 04:46:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8dc6d960ffedc1fa04e80cfe16ca17c0 SHA-1: 9b67293c44a9383dbfed43eabf33ed454ed9daf6 SHA-256: 1b8355b753af1f6e61c8f79cda6e590c4222c0903c474d074a001a03453f61bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, characteristic of a link farm used to distribute phishing content or malware. The presence of external URIs and link farm heuristics strongly suggests an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9932

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 http://daedukgs.com/admin/fckeditor/data/file/20210627074926.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160b408a889f16---82304028328.pdf
    • https://belgradenightlife.info/wp-content/plugins/super-forms/uploads/php/files/kn92r7ebvd4optgvlp50m1lgsq/posukuzofagukoze.pdf
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c62d500e9d---sexuwiwaz.pdf
    • http://girisimcilikproje.com/resimler/files/fogababosegunijiwagavu.pdf
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/e060add7be9640a3fe5ec0301ef6ada7/14057987937.pdf
    • http://cimkezes.hu/uploads/ckfinder/userfiles/files/1505866856.pdf
    • http://hoadon-dientu.net/images/files/mivugisedukowenogiwoxu.pdf
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/e22cde022d47d4425bceea8e4dfac0ca/lupokukigifuv.pdf
    • https://tecnicadovolante.com/images/file/nigelonixezu.pdf
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a875996c677---telexokasumadoxapogerevap.pdf
    • http://hotelbelleepoque.bg/userfiles/file/loxafijizijeru.pdf
    • http://asupuro.com/user_data/image//file/namuro.pdf
    • https://ncsccalgary.com/userfiles/files/49603394020.pdf
    • https://ludifrance.fr/userfiles/file/40000170013.pdf
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/ec71a41b172d2eb55f59187df4a1b0d2/42696565782.pdf
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/f86a1d2fc96a9c0811f7f77d769abec0/9046152716.pdf
    • http://rld-carbon.ru/file/22836394076.pdf
    • https://www.cifphosteleriayturismo.es/ckfinder/userfiles/files/wuwunotekugamafux.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba9c256ab47---44422052691.pdf
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/c25a52e54bd18537b153e721d54dc44f/gajefetexilameja.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160b1603698b95---5899775881.pdf
    • http://divorce-difficile.fr/userfiles/file/nixetizuxokeserul.pdf
    • http://purofirstli.net/userfiles/file/pesaburotevukajix.pdf
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/7d32e2de6e141282bd11e754f60b08fe/18133411243.pdf
    • https://www.azulejositurry.com/wp-content/plugins/super-forms/uploads/php/files/ddjmge57je0d56g9r8f9fn0sk2/24294809397.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=how+many+carbs+are+in+a+soft+taco
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a2f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A2F 16792 bytes
font_01_sfnt_off00012246.bin
fa790ed854f1aea1563ca563ec1211128be8137bc12c3a59e63d72ab8b45759c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12246 10780 bytes
font_02_sfnt_off00013b2b.bin
ecb0f532bce1b250e3afea01830e181304395728328fbe80bd85998133fbd6ef
pdf-font-stream PDF embedded font (sfnt) at offset 0x13B2B 17128 bytes