Malicious PDF — malware analysis report

Static analysis result for SHA-256 40b3a17fc1de9a3e…

MALICIOUS

PDF

69.7 KB Created: 2020-07-18 22:08:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 2f1eb8db4405826d8621ba9e94a356bd SHA-1: f3eb1fecd5b2636c89b6cd1670773bd111c40482 SHA-256: 40b3a17fc1de9a3e23b042f7fb6c54c414bb198d00882f89a1dcd6323d9874d4
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF was flagged as malicious due to a large number of embedded links, many of which point to a redirector service. The document body contains garbled text, suggesting it is not intended for direct user consumption but rather as a container for malicious links. The primary malicious IOC is the redirector URL, which is likely used to funnel victims to further stages of an attack.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://ttraff.cc/wb?keyword=angulos%20de%20elevacion%20y%20depresion%20problemas%20resueltos%20pdf In PDF document text
    • http://files.edhgs.com/uploads/1/3/1/4/131408529/lujaremokike_nezuki_derunelizaxeti_kelabij.pdfIn PDF document text
    • http://files.itschima.com/uploads/1/3/1/4/131454098/fetil-kuzozozinawedap.pdfIn PDF document text
    • http://files.kgoetztraining.com/uploads/1/3/1/8/131871871/2689137.pdfIn PDF document text
    • http://files.doclaurayoung.com/uploads/1/3/1/4/131483491/dafepikefafemi.pdfIn PDF document text
    • http://files.lauracarolyn.com/uploads/1/3/1/4/131437983/kumilikiraseber-jufinoduse-gutujo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/kivamusefelozadadazub.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/4957/3784/files/6413321228.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/87932640634.pdfIn PDF document text
    • https://detixuge.files.wordpress.com/2020/06/vinagatodolemojusin.pdfIn PDF document text
    • https://nupatam.files.wordpress.com/2020/06/kedugiged.pdfIn PDF document text
    • https://gonitoji.files.wordpress.com/2020/07/60283462509.pdfIn PDF document text
    • https://wasukajam.files.wordpress.com/2020/07/sosisotunonekoseda.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/9490/7810/files/semupimevakobozi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/9654/7230/files/dadovagirowezedunap.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/3724/5086/files/kesalun.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/97697777452.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/7977/8979/files/60386156675.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/7713/9613/files/19620912701.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c605.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC605 5648 bytes
SHA-256: 6e3ac814622e4954d44392f922ae13957aee8f2b403e029fa34fed0157572c3d
font_01_sfnt_off0000d926.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD926 15060 bytes
SHA-256: a107611fcdc810c781b4367ae38e4bc49954c42e34f4f8a9faec608699525f0f